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(....);
  }
}

得分为2，因为ExecuteAction出现2次。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的位置以及它将在何处结束。是否可以改变我的做法？

谢谢。

Answer 1

下面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显示的次数？有点像：

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();
    }

代码编译方法中函数执行的计数

2 个答案: