如何在 Mono Cecil 中创建“字典”

Question

我有一个像这样的 DLL 类：

namespace ClassLibrary1
{
    public static class Class1
    {
        public static Dictionary<string, string> GetDictionary()
        {
            return null;
        }
    }
}

在另一个程序中，我想覆盖ClassLibrary1.dll GetDictionary()方法以使用 Mono Cecil 返回我的Dictionary 。
我有的例子：

Dictionary<string, string> dictionary = new Dictionary<string, string>();
dictionary.Add("first", "1");
dictionary.Add("second", "2");

所以我想要GetDictionary返回dictionary 。

如何在 Mono cecil 中做到这一点？

Answer 1

正如我在上面评论的那样，您可以使用https://cecilifier.me并传递您的 C# 代码来生成对 Mono.Cecil 的等效调用：

using Mono.Cecil;
using Mono.Cecil.Cil;
using Mono.Cecil.Rocks;
using System; 
using System.Linq;
using BindingFlags = System.Reflection.BindingFlags;

using Cecilifier.Runtime;

public class SnippetRunner
{
    public static void Main(string[] args)
    {
        var assembly = AssemblyDefinition.CreateAssembly(new AssemblyNameDefinition("name", Version.Parse("1.0.0.0")), "moduleName", ModuleKind.Dll);
        var t1 = new TypeDefinition("", "Foo", TypeAttributes.AnsiClass | TypeAttributes.BeforeFieldInit | TypeAttributes.NotPublic, assembly.MainModule.TypeSystem.Object);
        assembly.MainModule.Types.Add(t1);
        t1.BaseType = assembly.MainModule.TypeSystem.Object;
        var Foo_ctor_ = new MethodDefinition(".ctor", MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.RTSpecialName | MethodAttributes.SpecialName, assembly.MainModule.TypeSystem.Void);
        t1.Methods.Add(Foo_ctor_);
        var il1 = Foo_ctor_.Body.GetILProcessor();
        var Ldarg_02 = il1.Create(OpCodes.Ldarg_0);
        il1.Append(Ldarg_02);
        var Call3 = il1.Create(OpCodes.Call, assembly.MainModule.ImportReference(TypeHelpers.DefaultCtorFor(t1.BaseType)));
        il1.Append(Call3);
        var Ret4 = il1.Create(OpCodes.Ret);
        il1.Append(Ret4);

        var Foo_F_ = new MethodDefinition("F", MethodAttributes.Private | MethodAttributes.HideBySig, assembly.MainModule.TypeSystem.Void);
        t1.Methods.Add(Foo_F_);
        var il_Foo_F_ = Foo_F_.Body.GetILProcessor();
        var lv_dictionary5 = new VariableDefinition(assembly.MainModule.ImportReference(typeof(System.Collections.Generic.Dictionary<,>)).MakeGenericInstanceType(assembly.MainModule.TypeSystem.String,assembly.MainModule.TypeSystem.String));
        Foo_F_.Body.Variables.Add(lv_dictionary5);
        var Newobj6 = il_Foo_F_.Create(OpCodes.Newobj, assembly.MainModule.ImportReference(TypeHelpers.ResolveMethod("System.Private.CoreLib", "System.Collections.Generic.Dictionary`2", ".ctor",System.Reflection.BindingFlags.Default|System.Reflection.BindingFlags.Instance|System.Reflection.BindingFlags.Public,"System.String,System.String")));
        il_Foo_F_.Append(Newobj6);
        var Stloc7 = il_Foo_F_.Create(OpCodes.Stloc, lv_dictionary5);
        il_Foo_F_.Append(Stloc7);

// dictionary.Add("first", "1");
        var Ldloc8 = il_Foo_F_.Create(OpCodes.Ldloc, lv_dictionary5);
        il_Foo_F_.Append(Ldloc8);
        var Callvirt9 = il_Foo_F_.Create(OpCodes.Callvirt, assembly.MainModule.ImportReference(TypeHelpers.ResolveMethod("System.Private.CoreLib", "System.Collections.Generic.Dictionary`2", "Add",System.Reflection.BindingFlags.Default|System.Reflection.BindingFlags.Instance|System.Reflection.BindingFlags.Public,"System.String,System.String", "System.String", "System.String")));
        var Ldstr10 = il_Foo_F_.Create(OpCodes.Ldstr, "first");
        il_Foo_F_.Append(Ldstr10);
        var Ldstr11 = il_Foo_F_.Create(OpCodes.Ldstr, "1");
        il_Foo_F_.Append(Ldstr11);
        il_Foo_F_.Append(Callvirt9);

// dictionary.Add("second", "2");
        var Ldloc12 = il_Foo_F_.Create(OpCodes.Ldloc, lv_dictionary5);
        il_Foo_F_.Append(Ldloc12);
        var Callvirt13 = il_Foo_F_.Create(OpCodes.Callvirt, assembly.MainModule.ImportReference(TypeHelpers.ResolveMethod("System.Private.CoreLib", "System.Collections.Generic.Dictionary`2", "Add",System.Reflection.BindingFlags.Default|System.Reflection.BindingFlags.Instance|System.Reflection.BindingFlags.Public,"System.String,System.String", "System.String", "System.String")));
        var Ldstr14 = il_Foo_F_.Create(OpCodes.Ldstr, "second");
        il_Foo_F_.Append(Ldstr14);
        var Ldstr15 = il_Foo_F_.Create(OpCodes.Ldstr, "2");
        il_Foo_F_.Append(Ldstr15);
        il_Foo_F_.Append(Callvirt13);
        var Ret16 = il_Foo_F_.Create(OpCodes.Ret);
        il_Foo_F_.Append(Ret16);

        assembly.Write(args[0]);
    }
}