字段有静态字段和非静态字段之分,它们的加载保存指令也是不一样的,并且非静态字段要生成this。
静态字段的加载
加载静态字段的指令是Ldsfld。
ilGenerator.Emit(OpCodes.Ldsfld, <FieldBuilder>);
实际例子
ilGenerator.Emit(OpCodes.Ldsfld, areaFieldBuilder);
ilGenerator.Emit(OpCodes.Call, writeStringLineMethod);
静态字段的保存
保存静态字段的指令是Stsfld。
ilGenerator.Emit(OpCodes.Stsfld, <FieldBuilder>);
实际例子
ilGenerator.Emit(OpCodes.Ldstr,"New York"); ilGenerator.Emit(OpCodes.Stsfld, areaFieldBuilder);
实例字段的加载
加载静态字段的指令是Ldsfld,必须要在第一步生成Ldarg_0指令。
ilGenerator.Emit(OpCodes.Ldsfld, <FieldBuilder>);
实际例子
ilGenerator.Emit(OpCodes.Ldarg_0);//生成this ilGenerator.Emit(OpCodes.Ldfld, areaFieldBuilder); ilGenerator.Emit(OpCodes.Call, writeStringLineMethod);
实例字段的保存
保存静态字段的指令是Stsfld,必须要在第一步生成Ldarg_0指令。
ilGenerator.Emit(OpCodes.Stsfld, <FieldBuilder>);
实际例子
ilGenerator.Emit(OpCodes.Ldarg_0);//生成this ilGenerator.Emit(OpCodes.Ldstr, "Tom"); ilGenerator.Emit(OpCodes.Stfld, nameFieldBuilder);
一个完整的程序如下
using System; using System.Reflection; using System.Reflection.Emit; namespace LX1_ILDemo { class Demo09_FieldLoadStorm { static string binaryName = "Demo09_FieldLoadStorm.dll"; static string namespaceName = "LX1_ILDemo"; static string typeName = "FieldLoadStorm"; static AssemblyBuilder assemblyBuilder; static ModuleBuilder moduleBuilder; static TypeBuilder typeBuilder; static MethodBuilder testMethod; static ILGenerator ilGenerator; static void Emit_IL() { /* protected string Area; */ FieldBuilder areaFieldBuilder = typeBuilder.DefineField("Area", typeof(string), FieldAttributes.Public | FieldAttributes.Static); /* private string Name; */ FieldBuilder nameFieldBuilder = typeBuilder.DefineField("Name", typeof(string), FieldAttributes.Public); testMethod = typeBuilder.DefineMethod("Test", MethodAttributes.Public, typeof(void), new Type[] { }); ilGenerator = testMethod.GetILGenerator(); MethodInfo writeStringLineMethod = typeof(Console).GetMethod("WriteLine", new Type[] { typeof(string) }); ilGenerator.Emit(OpCodes.Ldstr,"New York"); ilGenerator.Emit(OpCodes.Stsfld, areaFieldBuilder); ilGenerator.Emit(OpCodes.Ldsfld, areaFieldBuilder); ilGenerator.Emit(OpCodes.Call, writeStringLineMethod); ilGenerator.Emit(OpCodes.Ldarg_0);//生成this ilGenerator.Emit(OpCodes.Ldstr, "Tom"); ilGenerator.Emit(OpCodes.Stfld, nameFieldBuilder); ilGenerator.Emit(OpCodes.Ldarg_0);//生成this ilGenerator.Emit(OpCodes.Ldfld, areaFieldBuilder); ilGenerator.Emit(OpCodes.Call, writeStringLineMethod); ilGenerator.Emit(OpCodes.Ret); } public static void Generate() { InitAssembly(); typeBuilder = moduleBuilder.DefineType(namespaceName + "." + typeName, TypeAttributes.Public); Emit_IL(); SaveAssembly(); Console.WriteLine("生成成功"); } static void InitAssembly() { AssemblyName assemblyName = new AssemblyName(namespaceName); assemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.RunAndSave); moduleBuilder = assemblyBuilder.DefineDynamicModule(assemblyName.Name, binaryName); } static void SaveAssembly() { Type t = typeBuilder.CreateType(); //完成Type,这是必须的 assemblyBuilder.Save(binaryName); } } }