| <!DOCTYPE html><html class="default" lang="en" data-base=".."><head><meta charset="utf-8"/><meta http-equiv="x-ua-compatible" content="IE=edge"/><title>docs/guides/form-validation | react-declarative</title><meta name="description" content="Documentation for react-declarative"/><meta name="viewport" content="width=device-width, initial-scale=1"/><link rel="stylesheet" href="../assets/style.css"/><link rel="stylesheet" href="../assets/highlight.css"/><script defer src="../assets/main.js"></script><script async src="../assets/icons.js" id="tsd-icons-script"></script><script async src="../assets/search.js" id="tsd-search-script"></script><script async src="../assets/navigation.js" id="tsd-nav-script"></script><script async src="../assets/hierarchy.js" id="tsd-hierarchy-script"></script></head><body><script>document.documentElement.dataset.theme = localStorage.getItem("tsd-theme") || "os";document.body.style.display="none";setTimeout(() => app?app.showPage():document.body.style.removeProperty("display"),500)</script><header class="tsd-page-toolbar"><div class="tsd-toolbar-contents container"><div class="table-cell" id="tsd-search"><div class="field"><label for="tsd-search-field" class="tsd-widget tsd-toolbar-icon search no-caption"><svg width="16" height="16" viewBox="0 0 16 16" fill="none" aria-hidden="true"><use href="../assets/icons.svg#icon-search"></use></svg></label><input type="text" id="tsd-search-field" aria-label="Search"/></div><div class="field"><div id="tsd-toolbar-links"></div></div><ul class="results"><li class="state loading">Preparing search index...</li><li class="state failure">The search index is not available</li></ul><a href="../index.html" class="title">react-declarative</a></div><div class="table-cell" id="tsd-widgets"><a href="#" class="tsd-widget tsd-toolbar-icon menu no-caption" data-toggle="menu" aria-label="Menu"><svg width="16" height="16" viewBox="0 0 16 16" fill="none" aria-hidden="true"><use href="../assets/icons.svg#icon-menu"></use></svg></a></div></div></header><div class="container container-main"><div class="col-content"><div class="tsd-page-title"><ul class="tsd-breadcrumb"><li><a href="../modules.html">react-declarative</a></li><li><a href="docs_guides_form-validation.html">docs/guides/form-validation</a></li></ul></div><div class="tsd-panel tsd-typography"><a id="validating-form-fields-with-isinvalid-and-isincorrect" class="tsd-anchor"></a><h1 class="tsd-anchor-link">Validating form fields with isInvalid and isIncorrect<a href="#validating-form-fields-with-isinvalid-and-isincorrect" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h1><p>Validation in react-declarative lives entirely inside your field schema — there is no separate validation library to configure. Each field can declare its own <code>isInvalid</code> callback that receives the current form data and returns either a string error message or <code>null</code>. This keeps validation logic co-located with the field it describes and makes the schema self-documenting.</p> |
| <a id="the-isinvalid-callback" class="tsd-anchor"></a><h2 class="tsd-anchor-link">The <code>isInvalid</code> callback<a href="#the-isinvalid-callback" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h2><p>Add <code>isInvalid</code> to any field. The function receives the entire form data object as its first argument, so you can validate a field against any other field's value. Return a non-null string to mark the field invalid; return <code>null</code> to mark it valid.</p> |
| <pre><code class="tsx"><span class="hl-0">import</span><span class="hl-1"> { </span><span class="hl-2">FieldType</span><span class="hl-1">, </span><span class="hl-2">TypedField</span><span class="hl-1"> } </span><span class="hl-0">from</span><span class="hl-1"> </span><span class="hl-3">'react-declarative'</span><span class="hl-1">;</span><br/><br/><span class="hl-4">const</span><span class="hl-1"> </span><span class="hl-10">fields</span><span class="hl-1">: </span><span class="hl-7">TypedField</span><span class="hl-1">[] = [</span><br/><span class="hl-1"> {</span><br/><span class="hl-1"> </span><span class="hl-2">type:</span><span class="hl-1"> </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-2">name:</span><span class="hl-1"> </span><span class="hl-3">'email'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-2">title:</span><span class="hl-1"> </span><span class="hl-3">'Email'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-5">isInvalid</span><span class="hl-1">({ </span><span class="hl-2">email</span><span class="hl-1"> }) {</span><br/><span class="hl-1"> </span><span class="hl-4">const</span><span class="hl-1"> </span><span class="hl-10">expr</span><span class="hl-1"> =</span><span class="hl-11"> /</span><span class="hl-12">^</span><span class="hl-13">[</span><span class="hl-14">\w</span><span class="hl-11">-.</span><span class="hl-13">]</span><span class="hl-15">+</span><span class="hl-11">@</span><span class="hl-13">([</span><span class="hl-11">\w-</span><span class="hl-13">]</span><span class="hl-15">+</span><span class="hl-14">\.</span><span class="hl-13">)</span><span class="hl-15">+</span><span class="hl-13">[</span><span class="hl-11">\w-</span><span class="hl-13">]</span><span class="hl-15">{2,4}</span><span class="hl-12">$</span><span class="hl-11">/</span><span class="hl-4">g</span><span class="hl-1">;</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (!</span><span class="hl-2">expr</span><span class="hl-1">.</span><span class="hl-5">test</span><span class="hl-1">(</span><span class="hl-2">email</span><span class="hl-1">)) {</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-3">'Invalid email address'</span><span class="hl-1">;</span><br/><span class="hl-1"> }</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-4">null</span><span class="hl-1">;</span><br/><span class="hl-1"> },</span><br/><span class="hl-1"> },</span><br/><span class="hl-1">];</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <blockquote> |
| <p><strong>Note:</strong> The <code>isInvalid</code> function receives the <strong>whole data object</strong>, not just the field's own value. Destructure what you need from the first argument.</p> |
| </blockquote> |
| <a id="cross-field-validation" class="tsd-anchor"></a><h2 class="tsd-anchor-link">Cross-field validation<a href="#cross-field-validation" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h2><p>Because <code>isInvalid</code> sees all form data, you can write rules that span multiple fields. The following example rejects the combination where <code>from</code> is greater than <code>to</code>:</p> |
| <pre><code class="tsx"><span class="hl-4">const</span><span class="hl-1"> </span><span class="hl-10">fields</span><span class="hl-1">: </span><span class="hl-7">TypedField</span><span class="hl-1">[] = [</span><br/><span class="hl-1"> {</span><br/><span class="hl-1"> </span><span class="hl-2">type:</span><span class="hl-1"> </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-2">name:</span><span class="hl-1"> </span><span class="hl-3">'from'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-2">title:</span><span class="hl-1"> </span><span class="hl-3">'From'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-5">isInvalid</span><span class="hl-2">:</span><span class="hl-1"> ({ </span><span class="hl-2">from</span><span class="hl-1">, </span><span class="hl-2">to</span><span class="hl-1"> }) </span><span class="hl-4">=></span><span class="hl-1"> {</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (!</span><span class="hl-2">from</span><span class="hl-1"> || !</span><span class="hl-2">to</span><span class="hl-1">) </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-4">null</span><span class="hl-1">;</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (</span><span class="hl-5">parseInt</span><span class="hl-1">(</span><span class="hl-2">from</span><span class="hl-1">) > </span><span class="hl-5">parseInt</span><span class="hl-1">(</span><span class="hl-2">to</span><span class="hl-1">)) {</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-3">'From must not exceed To'</span><span class="hl-1">;</span><br/><span class="hl-1"> }</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-4">null</span><span class="hl-1">;</span><br/><span class="hl-1"> },</span><br/><span class="hl-1"> </span><span class="hl-2">defaultValue:</span><span class="hl-1"> </span><span class="hl-3">'50'</span><span class="hl-1">,</span><br/><span class="hl-1"> },</span><br/><span class="hl-1"> {</span><br/><span class="hl-1"> </span><span class="hl-2">type:</span><span class="hl-1"> </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-2">name:</span><span class="hl-1"> </span><span class="hl-3">'to'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-2">title:</span><span class="hl-1"> </span><span class="hl-3">'To'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-5">isInvalid</span><span class="hl-2">:</span><span class="hl-1"> ({ </span><span class="hl-2">from</span><span class="hl-1">, </span><span class="hl-2">to</span><span class="hl-1"> }) </span><span class="hl-4">=></span><span class="hl-1"> {</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (!</span><span class="hl-2">from</span><span class="hl-1"> || !</span><span class="hl-2">to</span><span class="hl-1">) </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-4">null</span><span class="hl-1">;</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (</span><span class="hl-5">parseInt</span><span class="hl-1">(</span><span class="hl-2">from</span><span class="hl-1">) > </span><span class="hl-5">parseInt</span><span class="hl-1">(</span><span class="hl-2">to</span><span class="hl-1">)) {</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-3">'To must not be less than From'</span><span class="hl-1">;</span><br/><span class="hl-1"> }</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-4">null</span><span class="hl-1">;</span><br/><span class="hl-1"> },</span><br/><span class="hl-1"> </span><span class="hl-2">defaultValue:</span><span class="hl-1"> </span><span class="hl-3">'150'</span><span class="hl-1">,</span><br/><span class="hl-1"> },</span><br/><span class="hl-1">];</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <a id="async-validation" class="tsd-anchor"></a><h2 class="tsd-anchor-link">Async validation<a href="#async-validation" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h2><p><code>isInvalid</code> can be <code>async</code>. React-declarative debounces form state change events, so async validators run efficiently without hammering your server on every keystroke.</p> |
| <pre><code class="tsx"><span class="hl-1">{</span><br/><span class="hl-1"> </span><span class="hl-20">type</span><span class="hl-1">: </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">name</span><span class="hl-1">: </span><span class="hl-3">'username'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">title</span><span class="hl-1">: </span><span class="hl-3">'Username'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">isInvalid</span><span class="hl-1">: </span><span class="hl-4">async</span><span class="hl-1"> ({ </span><span class="hl-2">username</span><span class="hl-1"> }) </span><span class="hl-4">=></span><span class="hl-1"> {</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (!</span><span class="hl-2">username</span><span class="hl-1">) </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-3">'Username is required'</span><span class="hl-1">;</span><br/><span class="hl-1"> </span><span class="hl-4">const</span><span class="hl-1"> </span><span class="hl-10">taken</span><span class="hl-1"> = </span><span class="hl-0">await</span><span class="hl-1"> </span><span class="hl-5">checkUsernameAvailability</span><span class="hl-1">(</span><span class="hl-2">username</span><span class="hl-1">);</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (</span><span class="hl-2">taken</span><span class="hl-1">) </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-3">'This username is already taken'</span><span class="hl-1">;</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-4">null</span><span class="hl-1">;</span><br/><span class="hl-1"> },</span><br/><span class="hl-1">}</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <blockquote> |
| <p><strong>Tip:</strong> Debouncing is built in — form state change events are rate-limited so your async validator won't fire on every single keystroke.</p> |
| </blockquote> |
| <a id="non-blocking-validation-with-isincorrect" class="tsd-anchor"></a><h2 class="tsd-anchor-link">Non-blocking validation with <code>isIncorrect</code><a href="#non-blocking-validation-with-isincorrect" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h2><p>Use <code>isIncorrect</code> when you want to show a warning (for example, a spell-check suggestion) without blocking the save button. The error renders in the UI but the form can still be submitted.</p> |
| <pre><code class="tsx"><span class="hl-1">{</span><br/><span class="hl-1"> </span><span class="hl-20">type</span><span class="hl-1">: </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">name</span><span class="hl-1">: </span><span class="hl-3">'description'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">title</span><span class="hl-1">: </span><span class="hl-3">'Description'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">isIncorrect</span><span class="hl-1">: ({ </span><span class="hl-2">description</span><span class="hl-1"> }) </span><span class="hl-4">=></span><span class="hl-1"> {</span><br/><span class="hl-1"> </span><span class="hl-0">if</span><span class="hl-1"> (</span><span class="hl-2">description</span><span class="hl-1"> && </span><span class="hl-2">description</span><span class="hl-1">.</span><span class="hl-2">length</span><span class="hl-1"> < </span><span class="hl-16">20</span><span class="hl-1">) {</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-3">'Descriptions are typically at least 20 characters'</span><span class="hl-1">;</span><br/><span class="hl-1"> }</span><br/><span class="hl-1"> </span><span class="hl-0">return</span><span class="hl-1"> </span><span class="hl-4">null</span><span class="hl-1">;</span><br/><span class="hl-1"> },</span><br/><span class="hl-1">}</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <a id="isrequired-vs-custom-isinvalid" class="tsd-anchor"></a><h2 class="tsd-anchor-link"><code>isRequired</code> vs custom <code>isInvalid</code><a href="#isrequired-vs-custom-isinvalid" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h2><p>The <code>IValidation</code> object on the <code>validation</code> prop provides a shorthand for common rules including required fields:</p> |
| <pre><code class="tsx"><span class="hl-1">{</span><br/><span class="hl-1"> </span><span class="hl-20">type</span><span class="hl-1">: </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">name</span><span class="hl-1">: </span><span class="hl-3">'firstName'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">title</span><span class="hl-1">: </span><span class="hl-3">'First name'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">validation</span><span class="hl-1">: {</span><br/><span class="hl-1"> </span><span class="hl-20">required</span><span class="hl-1">: </span><span class="hl-4">true</span><span class="hl-1">,</span><br/><span class="hl-1"> },</span><br/><span class="hl-1">}</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <p>Use <code>isInvalid</code> when you need logic that goes beyond a simple required check — pattern matching, cross-field comparisons, or async server lookups. Use <code>validation.required</code> for the straightforward case.</p> |
| <a id="when-does-validation-fire" class="tsd-anchor"></a><h3 class="tsd-anchor-link">When does validation fire?<a href="#when-does-validation-fire" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h3><p>Validation runs whenever the form data changes. The library debounces state updates, so rapid user input (typing) is batched before <code>isInvalid</code> is called. Validation also runs on the initial render if the field has a <code>defaultValue</code> and <code>dirty</code> is set to <code>true</code> on that field.</p> |
| <a id="the-dirty-flag" class="tsd-anchor"></a><h3 class="tsd-anchor-link">The dirty flag<a href="#the-dirty-flag" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h3><p>By default, a field waits for the user to focus and blur it before showing an error. Set <code>dirty: true</code> on a field to skip this waiting period and show validation errors immediately, even before the user has interacted with the field.</p> |
| <pre><code class="tsx"><span class="hl-1">{</span><br/><span class="hl-1"> </span><span class="hl-20">type</span><span class="hl-1">: </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">name</span><span class="hl-1">: </span><span class="hl-3">'email'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">dirty</span><span class="hl-1">: </span><span class="hl-4">true</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-5">isInvalid</span><span class="hl-1">({ </span><span class="hl-2">email</span><span class="hl-1"> }) {</span><br/><span class="hl-1"> </span><span class="hl-17">// fires immediately, not just after blur</span><br/><span class="hl-1"> },</span><br/><span class="hl-1">}</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <a id="reacting-to-form-invalidity" class="tsd-anchor"></a><h2 class="tsd-anchor-link">Reacting to form invalidity<a href="#reacting-to-form-invalidity" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h2><p>Pass an <code>invalidity</code> callback on a field to be notified when that field fails validation. This is useful for disabling a submit button or showing a banner.</p> |
| <pre><code class="tsx"><span class="hl-1">{</span><br/><span class="hl-1"> </span><span class="hl-20">type</span><span class="hl-1">: </span><span class="hl-2">FieldType</span><span class="hl-1">.</span><span class="hl-2">Text</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-20">name</span><span class="hl-1">: </span><span class="hl-3">'email'</span><span class="hl-1">,</span><br/><span class="hl-1"> </span><span class="hl-5">isInvalid</span><span class="hl-1">({ </span><span class="hl-2">email</span><span class="hl-1"> }) { </span><span class="hl-17">/* ... */</span><span class="hl-1"> },</span><br/><span class="hl-1"> </span><span class="hl-5">invalidity</span><span class="hl-1">(</span><span class="hl-2">name</span><span class="hl-1">, </span><span class="hl-2">errorMessage</span><span class="hl-1">, </span><span class="hl-2">payload</span><span class="hl-1">) {</span><br/><span class="hl-1"> </span><span class="hl-2">console</span><span class="hl-1">.</span><span class="hl-5">log</span><span class="hl-1">(</span><span class="hl-3">`</span><span class="hl-4">${</span><span class="hl-2">name</span><span class="hl-4">}</span><span class="hl-3"> is invalid: </span><span class="hl-4">${</span><span class="hl-2">errorMessage</span><span class="hl-4">}</span><span class="hl-3">`</span><span class="hl-1">);</span><br/><span class="hl-1"> },</span><br/><span class="hl-1">}</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <p>The <code><One /></code> component also exposes an <code>invalidity</code> prop at the form level:</p> |
| <pre><code class="tsx"><span class="hl-6"><</span><span class="hl-7">One</span><br/><span class="hl-1"> </span><span class="hl-8">fields</span><span class="hl-1">=</span><span class="hl-4">{</span><span class="hl-2">fields</span><span class="hl-4">}</span><br/><span class="hl-1"> </span><span class="hl-8">handler</span><span class="hl-1">=</span><span class="hl-4">{</span><span class="hl-9">() </span><span class="hl-4">=></span><span class="hl-9"> </span><span class="hl-2">initialData</span><span class="hl-4">}</span><br/><span class="hl-1"> </span><span class="hl-8">invalidity</span><span class="hl-1">=</span><span class="hl-4">{</span><span class="hl-9">(</span><span class="hl-2">name</span><span class="hl-9">, </span><span class="hl-2">errorMessage</span><span class="hl-9">) </span><span class="hl-4">=></span><span class="hl-9"> {</span><br/><span class="hl-9"> </span><span class="hl-5">setIsFormValid</span><span class="hl-9">(</span><span class="hl-4">false</span><span class="hl-9">);</span><br/><span class="hl-9"> }</span><span class="hl-4">}</span><br/><span class="hl-6">/></span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <a id="reflecting-visible-fields-with-getavailablefields" class="tsd-anchor"></a><h2 class="tsd-anchor-link">Reflecting visible fields with <code>getAvailableFields</code><a href="#reflecting-visible-fields-with-getavailablefields" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></h2><p>When fields are conditionally hidden, you may want to validate or export only the data that is currently visible. <code>getAvailableFields</code> returns the subset of fields whose <code>isVisible</code> predicate is currently truthy.</p> |
| <pre><code class="tsx"><span class="hl-0">import</span><span class="hl-1"> { </span><span class="hl-2">getAvailableFields</span><span class="hl-1"> } </span><span class="hl-0">from</span><span class="hl-1"> </span><span class="hl-3">'react-declarative'</span><span class="hl-1">;</span><br/><br/><span class="hl-4">const</span><span class="hl-1"> </span><span class="hl-10">visibleFields</span><span class="hl-1"> = </span><span class="hl-5">getAvailableFields</span><span class="hl-1">(</span><span class="hl-2">fields</span><span class="hl-1">, </span><span class="hl-2">formData</span><span class="hl-1">, </span><span class="hl-2">payload</span><span class="hl-1">);</span><br/><span class="hl-4">const</span><span class="hl-1"> </span><span class="hl-10">fieldNames</span><span class="hl-1"> = </span><span class="hl-2">visibleFields</span><span class="hl-1">.</span><span class="hl-5">map</span><span class="hl-1">((</span><span class="hl-2">f</span><span class="hl-1">) </span><span class="hl-4">=></span><span class="hl-1"> </span><span class="hl-2">f</span><span class="hl-1">.</span><span class="hl-2">name</span><span class="hl-1">);</span><br/><span class="hl-17">// use fieldNames to strip hidden fields before submitting</span> |
| </code><button type="button">Copy</button></pre> |
|
|
| <blockquote> |
| <p><strong>Note:</strong> <code>getAvailableFields</code> is purely a reflection utility — it does not render anything. Use it at submit time to clean up data before sending it to your API.</p> |
| </blockquote> |
| </div></div><div class="col-sidebar"><div class="page-menu"><div class="tsd-navigation settings"><details class="tsd-accordion"><summary class="tsd-accordion-summary"><h3><svg width="20" height="20" viewBox="0 0 24 24" fill="none" aria-hidden="true"><use href="../assets/icons.svg#icon-chevronDown"></use></svg>Settings</h3></summary><div class="tsd-accordion-details"><div class="tsd-filter-visibility"><span class="settings-label">Member Visibility</span><ul id="tsd-filter-options"><li class="tsd-filter-item"><label class="tsd-filter-input"><input type="checkbox" id="tsd-filter-protected" name="protected"/><svg width="32" height="32" viewBox="0 0 32 32" aria-hidden="true"><rect class="tsd-checkbox-background" width="30" height="30" x="1" y="1" rx="6" fill="none"></rect><path class="tsd-checkbox-checkmark" d="M8.35422 16.8214L13.2143 21.75L24.6458 10.25" stroke="none" stroke-width="3.5" stroke-linejoin="round" fill="none"></path></svg><span>Protected</span></label></li><li class="tsd-filter-item"><label class="tsd-filter-input"><input type="checkbox" id="tsd-filter-inherited" name="inherited" checked/><svg width="32" height="32" viewBox="0 0 32 32" aria-hidden="true"><rect class="tsd-checkbox-background" width="30" height="30" x="1" y="1" rx="6" fill="none"></rect><path class="tsd-checkbox-checkmark" d="M8.35422 16.8214L13.2143 21.75L24.6458 10.25" stroke="none" stroke-width="3.5" stroke-linejoin="round" fill="none"></path></svg><span>Inherited</span></label></li><li class="tsd-filter-item"><label class="tsd-filter-input"><input type="checkbox" id="tsd-filter-external" name="external"/><svg width="32" height="32" viewBox="0 0 32 32" aria-hidden="true"><rect class="tsd-checkbox-background" width="30" height="30" x="1" y="1" rx="6" fill="none"></rect><path class="tsd-checkbox-checkmark" d="M8.35422 16.8214L13.2143 21.75L24.6458 10.25" stroke="none" stroke-width="3.5" stroke-linejoin="round" fill="none"></path></svg><span>External</span></label></li></ul></div><div class="tsd-theme-toggle"><label class="settings-label" for="tsd-theme">Theme</label><select id="tsd-theme"><option value="os">OS</option><option value="light">Light</option><option value="dark">Dark</option></select></div></div></details></div><details open class="tsd-accordion tsd-page-navigation"><summary class="tsd-accordion-summary"><h3><svg width="20" height="20" viewBox="0 0 24 24" fill="none" aria-hidden="true"><use href="../assets/icons.svg#icon-chevronDown"></use></svg>On This Page</h3></summary><div class="tsd-accordion-details"><a href="#validating-form-fields-with-isinvalid-and-isincorrect"><span>Validating form fields with is<wbr/>Invalid and is<wbr/>Incorrect</span></a><ul><li><a href="#the-isinvalid-callback"><span>The is<wbr/>Invalid callback</span></a></li><li><a href="#cross-field-validation"><span>Cross-<wbr/>field validation</span></a></li><li><a href="#async-validation"><span>Async validation</span></a></li><li><a href="#non-blocking-validation-with-isincorrect"><span>Non-<wbr/>blocking validation with is<wbr/>Incorrect</span></a></li><li><a href="#isrequired-vs-custom-isinvalid"><span>is<wbr/>Required vs custom is<wbr/>Invalid</span></a></li><li><ul><li><a href="#when-does-validation-fire"><span>When does validation fire?</span></a></li><li><a href="#the-dirty-flag"><span>The dirty flag</span></a></li></ul></li><li><a href="#reacting-to-form-invalidity"><span>Reacting to form invalidity</span></a></li><li><a href="#reflecting-visible-fields-with-getavailablefields"><span>Reflecting visible fields with get<wbr/>Available<wbr/>Fields</span></a></li></ul></div></details></div><div class="site-menu"><nav class="tsd-navigation"><a href="../modules.html">react-declarative</a><ul class="tsd-small-nested-navigation" id="tsd-nav-container"><li>Loading...</li></ul></nav></div></div></div><footer><p class="tsd-generator">Generated using <a href="https://typedoc.org/" target="_blank">TypeDoc</a></p></footer><div class="overlay"></div></body></html> |
|
|
