代码编译方法中的函数执行计数

Question

我想计算函数“ExecuteAction”在类方法中出现的次数。

public class A : B
{
  public void X()
  {
    ExecuteAction(....);
    ExecuteAction(....);
  }
}

因为 ExecuteAction 出现 2 次，所以得分为 2。我需要它，因为我构建了测试框架，并希望允许外部测试操作员知道当前步骤执行在哪里以及它将在哪里结束。是否可以做或应该改变我的方法？

谢谢。

Answer 1

以下是演示如何通过反射读取方法体并计算特定方法的所有调用的方法：

class Foo {
    public void SomeMethod() {
        ExecuteAction();
        ExecuteAction();
    }
    public void ExecuteAction() {
        //
    }
}
// --- Read the IL ---
var mInfo = typeof(Foo).GetMethod("SomeMethod");
var token = typeof(Foo).GetMethod("ExecuteAction").MetadataToken;

var methodBody = mInfo.GetMethodBody();
var rawIL = methodBody.GetILAsByteArray();

int counter = 0;
var reader = new ILReader(rawIL);
while(reader.Read(mInfo)) {
    if(reader.OpCode == OpCodes.Call && object.Equals(reader.MetadataToken, token)) {
        System.Console.WriteLine("Method \"{0}\" call detected", reader.Operand);
        counter++;
    }
}
System.Console.WriteLine("Total: {0}", counter);

ILReader 类实现如下（此特定任务的最小实现）：

class ILReader {
    readonly byte[] msil;
    int ptr;
    public ILReader(byte[] msil) {
        this.msil = msil;
    }
    public OpCode OpCode { get; private set; }
    public int MetadataToken { get; private set; }
    public object Operand { get; private set; }
    public bool Read(MethodInfo methodInfo) {
        if(ptr < msil.Length) {
            OpCode = ReadOpCode();
            Operand = ReadOperand(OpCode, methodInfo);
            return true;
        }
        return false;
    }
    OpCode ReadOpCode() {
        byte instruction = ReadByte();
        if(instruction != 254)
            return singleByteOpCode[instruction];
        else
            return doubleByteOpCode[ReadByte()];
    }
    object ReadOperand(OpCode code, MethodInfo methodInfo) {
        MetadataToken = 0;
        switch(code.OperandType) {
            case OperandType.InlineMethod:
                MetadataToken = ReadInt();
                System.Type[] methodArgs = null;
                if(methodInfo.GetType() != typeof(ConstructorInfo))
                    methodArgs = methodInfo.GetGenericArguments();
                System.Type[] typeArgs = null;
                if(methodInfo.DeclaringType != null)
                    typeArgs = methodInfo.DeclaringType.GetGenericArguments();
                return methodInfo.Module.ResolveMember(MetadataToken, typeArgs, methodArgs);
        }
        return null;
    }
    byte ReadByte() {
        return msil[ptr++];
    }
    int ReadInt() {
        byte b1 = ReadByte();
        byte b2 = ReadByte();
        byte b3 = ReadByte();
        byte b4 = ReadByte();
        return (int)b1 | (((int)b2) << 8) | (((int)b3) << 16) | (((int)b4) << 24);
    }
    #region static
    static ILReader() {
            CreateOpCodes();
        }
    static OpCode[] singleByteOpCode;
    static OpCode[] doubleByteOpCode;
    static void CreateOpCodes() {
        singleByteOpCode = new OpCode[225];
        doubleByteOpCode = new OpCode[31];

        FieldInfo[] fields = GetOpCodeFields();

        for(int i = 0; i < fields.Length; i++) {
            OpCode code = (OpCode)fields[i].GetValue(null);
            if(code.OpCodeType == OpCodeType.Nternal)
                continue;

            if(code.Size == 1)
                singleByteOpCode[code.Value] = code;
            else
                doubleByteOpCode[code.Value & 0xff] = code;
        }
    }
    static FieldInfo[] GetOpCodeFields() {
        return typeof(OpCodes).GetFields(BindingFlags.Public | BindingFlags.Static);
    }
    #endregion static
}

Answer 2

为什么不编写一个脚本来计算您的函数在源代码中出现的次数？大致如下：

static void Main(string[] args)
    {
        int count = 0;
        using (StreamReader sr = new StreamReader(System.IO.File.OpenRead(@"<filepath>/Program.cs")))
        {
            while (sr.Peek()>0)
            {
                string line = sr.ReadLine();
                if (line.Contains("Function(") 
                    && !(line.Contains("class") || line.Contains("static") || line.Contains("public")))
                {
                    count++;
                }
            }
        }
        Console.WriteLine(count);
        Console.Read();
    }