File size: 5,154 Bytes
8e6f15c | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 | ## About
<!-- A description of the package and where one can find more documentation -->
This package provides a low-level .NET (ECMA-335) metadata reader and writer. It's geared for performance and is the ideal choice for building higher-level libraries that intend to provide their own object model, such as compilers. The metadata format is defined by the [ECMA-335 - Common Language Infrastructure (CLI)](http://www.ecma-international.org/publications/standards/Ecma-335.htm) specification and [its amendments](https://github.com/dotnet/runtime/blob/main/docs/design/specs/Ecma-335-Augments.md).
The `System.Reflection.Metadata` library is included in the .NET Runtime shared framework. The package can be installed when you need to use it in other target frameworks.
## How to Use
<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
The following example shows how to read assembly information using PEReader and MetadataReader.
```cs
using System;
using System.IO;
using System.Reflection.Metadata;
using System.Reflection.PortableExecutable;
class Program
{
static void Main()
{
// Open the Portable Executable (PE) file
using var fs = new FileStream("Example.dll", FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
using var peReader = new PEReader(fs);
// Display PE header information
PEHeader header = peReader.PEHeaders.PEHeader;
Console.WriteLine($"Image base: 0x{header.ImageBase:X}");
Console.WriteLine($"File alignment: 0x{header.FileAlignment:X}");
Console.WriteLine($"Subsystem: {header.Subsystem}");
// Display .NET metadata information
if (!peReader.HasMetadata)
{
Console.WriteLine("Image does not contain .NET metadata");
return;
}
MetadataReader mr = peReader.GetMetadataReader();
AssemblyDefinition ad = mr.GetAssemblyDefinition();
Console.WriteLine($"Assembly name: {ad.GetAssemblyName().ToString()}");
Console.WriteLine();
Console.WriteLine("Assembly attributes:");
foreach (CustomAttributeHandle attrHandle in ad.GetCustomAttributes())
{
CustomAttribute attr = mr.GetCustomAttribute(attrHandle);
// Display the attribute type full name
if (attr.Constructor.Kind == HandleKind.MethodDefinition)
{
MethodDefinition mdef = mr.GetMethodDefinition((MethodDefinitionHandle)attr.Constructor);
TypeDefinition tdef = mr.GetTypeDefinition(mdef.GetDeclaringType());
Console.WriteLine($"{mr.GetString(tdef.Namespace)}.{mr.GetString(tdef.Name)}");
}
else if (attr.Constructor.Kind == HandleKind.MemberReference)
{
MemberReference mref = mr.GetMemberReference((MemberReferenceHandle)attr.Constructor);
if (mref.Parent.Kind == HandleKind.TypeReference)
{
TypeReference tref = mr.GetTypeReference((TypeReferenceHandle)mref.Parent);
Console.WriteLine($"{mr.GetString(tref.Namespace)}.{mr.GetString(tref.Name)}");
}
else if (mref.Parent.Kind == HandleKind.TypeDefinition)
{
TypeDefinition tdef = mr.GetTypeDefinition((TypeDefinitionHandle)mref.Parent);
Console.WriteLine($"{mr.GetString(tdef.Namespace)}.{mr.GetString(tdef.Name)}");
}
}
}
}
}
```
## Main Types
<!-- The main types provided in this library -->
The main types provided by this library are:
* `System.Reflection.Metadata.MetadataReader`
* `System.Reflection.PortableExecutable.PEReader`
* `System.Reflection.Metadata.Ecma335.MetadataBuilder`
* `System.Reflection.PortableExecutable.PEBuilder`
* `System.Reflection.PortableExecutable.ManagedPEBuilder`
## Additional Documentation
<!-- Links to further documentation -->
* [System.Reflection.Metadata.MetadataReader](https://docs.microsoft.com/dotnet/api/system.reflection.metadata.metadatareader)
* [System.Reflection.PortableExecutable.PEReader](https://docs.microsoft.com/dotnet/api/system.reflection.portableexecutable.pereader)
* [System.Reflection.Metadata.Ecma335.MetadataBuilder](https://docs.microsoft.com/dotnet/api/system.reflection.metadata.ecma335.metadatabuilder)
* [System.Reflection.PortableExecutable.PEBuilder](https://docs.microsoft.com/dotnet/api/system.reflection.portableexecutable.pebuilder)
* [System.Reflection.PortableExecutable.ManagedPEBuilder](https://docs.microsoft.com/dotnet/api/system.reflection.portableexecutable.managedpebuilder)
## Feedback & Contributing
<!-- How to provide feedback on this package and contribute to it -->
System.Reflection.Metadata is released as open source under the [MIT license](https://licenses.nuget.org/MIT). Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime). |