从PDB文件检索本地变量名称
作者：互联网
我目前正在尝试从IL字节码和PDB文件中检索源代码,
我到了可以从IL和反射生成源代码的地步
我知道局部变量名称的名称包含在pdb文件中.
我的问题是如何找到它？我应该使用哪些库来处理pdb文件(如果有),或者我应该自己编写代码？在哪里可以找到有关pdb文件格式的信息？
当前在生成的源代码中,我正在使用本地变量的自动生成的值,但是我想更改它,因为我相信如果您有pdb文件可供使用,可以找到该信息.
我试图在Google上查看,但没有找到任何有用的信息.
预先感谢您的答复;)
解决方法:
这是使用System.Diagnostics.SymbolStore中的类型从MethodInfo读取局部变量名称的方法：
public class LocalVariableNameReader
{
Dictionary<int, string> _names = new Dictionary<int, string> ();
public string this [int index]
{
get
{
if (!_names.ContainsKey (index)) return null;
return _names [index];
}
}
public LocalVariableNameReader (MethodInfo m)
{
ISymbolReader symReader = SymUtil.GetSymbolReaderForFile (m.DeclaringType.Assembly.Location, null);
ISymbolMethod met = symReader.GetMethod (new SymbolToken (m.MetadataToken));
VisitLocals (met.RootScope);
}
void VisitLocals (ISymbolScope iSymbolScope)
{
foreach (var s in iSymbolScope.GetLocals ()) _names [s.AddressField1] = s.Name;
foreach (var c in iSymbolScope.GetChildren ()) VisitLocals (c);
}
}
SymUtil类来自this example.
编辑：上面的链接已损坏.从谷歌缓存：
A long time ago I was looking on how to process pdb files in order to
get additional information that reflection simply could not provide.
Now I stumped over a 5 year old post of Mike Stall
(07001)
and suddenly all became clear. I’ve put together a small example which
uses .net 4.0 to read the method body code as it is in the source code
from where the assembly was compiled. Mind you that in order for this
to work you have to have the pdb of the assembly available. Also
please make sure you add a refference to ISymWrapper and your project
is targeting .Net 4.0 framework, not .Net 4.0 Client.
using System;
using System.Diagnostics.SymbolStore;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
namespace PdbTest
{
class Program
{
static void Main(string[] args)
{
Assembly ass = Assembly.GetExecutingAssembly();
ISymbolReader symreader = SymUtil.GetSymbolReaderForFile(ass.Location, null);
MethodInfo m = ass.GetType("PdbTest.TestClass").GetMethod("GetStringRepresentation");
ISymbolMethod met = symreader.GetMethod(new SymbolToken(m.MetadataToken));
int count = met.SequencePointCount;
ISymbolDocument[] docs = new ISymbolDocument[count];
int[] offsets = new int[count];
int[] lines = new int[count];
int[] columns = new int[count];
int[] endlines = new int[count];
int[] endcolumns = new int[count];
met.GetSequencePoints(offsets, docs, lines, columns, endlines, endcolumns);
StreamReader reader = new StreamReader(docs[0].URL);
string[] linesOfCode = reader.ReadToEnd().Split('n');
reader.Close();
Console.WriteLine("The content of method PdbTest.TestClass.GetStringRepresentation");
for (int i = lines[0]; i < endlines[count - 1] - 1; i++)
{
Console.WriteLine(linesOfCode[i]);
}
}
}
#region test class
public enum MyEnum
{
Apples,
Oranges
}
public partial class TestClass
{
public string GetStringRepresentation(MyEnum e)
{
MyEnum e2 = MyEnum.Apples;
return e.ToString() + e2.ToString();
}
}
#endregion test class
#region Get a symbol reader for the given module
// Encapsulate a set of helper classes to get a symbol reader from a file.
// The symbol interfaces require an unmanaged metadata interface.
static class SymUtil
{
static class NativeMethods
{
[DllImport("ole32.dll")]
public static extern int CoCreateInstance(
[In] ref Guid rclsid,
[In, MarshalAs(UnmanagedType.IUnknown)] Object pUnkOuter,
[In] uint dwClsContext,
[In] ref Guid riid,
[Out, MarshalAs(UnmanagedType.Interface)] out Object ppv);
}
// Wrapper.
public static ISymbolReader GetSymbolReaderForFile(string pathModule, string searchPath)
{
return SymUtil.GetSymbolReaderForFile(
new System.Diagnostics.SymbolStore.SymBinder(), pathModule, searchPath);
}
// We demand Unmanaged code permissions because we're reading from the file
// system and calling out to the Symbol Reader
// @TODO - make this more specific.
[System.Security.Permissions.SecurityPermission(
System.Security.Permissions.SecurityAction.Demand,
Flags = System.Security.Permissions.SecurityPermissionFlag.UnmanagedCode)]
public static ISymbolReader GetSymbolReaderForFile(
System.Diagnostics.SymbolStore.SymBinder binder, string pathModule, string searchPath)
{
// Guids for imported metadata interfaces.
Guid dispenserClassID = new Guid(0xe5cb7a31, 0x7512, 0x11d2, 0x89,
0xce, 0x00, 0x80, 0xc7, 0x92, 0xe5, 0xd8); // CLSID_CorMetaDataDispenser
Guid dispenserIID = new Guid(0x809c652e, 0x7396, 0x11d2, 0x97, 0x71,
0x00, 0xa0, 0xc9, 0xb4, 0xd5, 0x0c); // IID_IMetaDataDispenser
Guid importerIID = new Guid(0x7dac8207, 0xd3ae, 0x4c75, 0x9b, 0x67,
0x92, 0x80, 0x1a, 0x49, 0x7d, 0x44); // IID_IMetaDataImport
// First create the Metadata dispenser.
object objDispenser;
NativeMethods.CoCreateInstance(ref dispenserClassID, null, 1,
ref dispenserIID, out objDispenser);
// Now open an Importer on the given filename. We'll end up passing this importer
// straight through to the Binder.
object objImporter;
IMetaDataDispenser dispenser = (IMetaDataDispenser)objDispenser;
dispenser.OpenScope(pathModule, 0, ref importerIID, out objImporter);
IntPtr importerPtr = IntPtr.Zero;
ISymbolReader reader;
try
{
// This will manually AddRef the underlying object, so we need to
// be very careful to Release it.
importerPtr = Marshal.GetComInterfaceForObject(objImporter,
typeof(IMetadataImport));
reader = binder.GetReader(importerPtr, pathModule, searchPath);
}
finally
{
if (importerPtr != IntPtr.Zero)
{
Marshal.Release(importerPtr);
}
}
return reader;
}
}
#region Metadata Imports
// We can use reflection-only load context to use reflection to query for
// metadata information rather
// than painfully import the com-classic metadata interfaces.
[Guid("809c652e-7396-11d2-9771-00a0c9b4d50c"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
[ComVisible(true)]
interface IMetaDataDispenser
{
// We need to be able to call OpenScope, which is the 2nd vtable slot.
// Thus we need this one placeholder here to occupy the first slot..
void DefineScope_Placeholder();
//STDMETHOD(OpenScope)( // Return code.
//LPCWSTR szScope, // [in] The scope to open.
// DWORD dwOpenFlags, // [in] Open mode flags.
// REFIID riid, // [in] The interface desired.
// IUnknown **ppIUnk) PURE; // [out] Return interface on success.
void OpenScope([In, MarshalAs(UnmanagedType.LPWStr)] String szScope,
[In] Int32 dwOpenFlags, [In] ref Guid riid,
[Out, MarshalAs(UnmanagedType.IUnknown)] out Object punk);
// Don't need any other methods.
}
// Since we're just blindly passing this interface through managed code to the Symbinder,
// we don't care about actually importing the specific methods.
// This needs to be public so that we can call Marshal.GetComInterfaceForObject() on
// it to get the underlying metadata pointer.
[Guid("7DAC8207-D3AE-4c75-9B67-92801A497D44"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
[ComVisible(true)]
[CLSCompliant(true)]
public interface IMetadataImport
{
// Just need a single placeholder method so that it doesn't complain
// about an empty interface.
void Placeholder();
}
#endregion
#endregion Get a symbol reader for the given module
}
标签：cil,c,net 来源： https://codeday.me/bug/20191208/2090817.html