在调用方法中检索原始变量/参数名称（类似于[CallerMemberName]属性）

Question

有没有办法在调用方法中获取变量/参数的原始名称，因为它已被命名？ 在某种程度上，它类似于[CallerMemberName]属性，但对于变量/参数。

更新2018.02：此问题类似于以下问题：1，2和3，但仍然无效，标准化解决方案在2018年初。 建议的解决方案：使用Expression<Func<T>>可以拥有 non-documented effects 并且非常 CPU密集型，因为将代码转换为表达式以获取原始名称变量只是一个简单的动作。 这就像创建一个1М大小的空数组来存储单个整数而不是简单的整数 - 非常无效（«згарматипогоробцям»）。

简短示例：

int ComplexMathMethod(int startPos, int endPos,
    int backgroundStartPos, int backgroundEndStart, 
    int squareStartPos, // …and other positions… )
{
    CheckPosition(startPos);
    CheckPosition(endPos);
    CheckPosition(backgroundStartPos);
    CheckPosition(backgroundEndStart);
    CheckPosition(squareStartPos);
    // …and so on…  
}

void CheckPosition(int position)
{
    bool isValidPosition = // complex check;
    if (!isValidPosition)
    {
        throw new ArgumentException(nameof(position));

        // --->>> It will be extremely convenient to automatically replace "nameof(position)" with original 
        // name of variable/argument from caller method, like: "startPos", "endPos", "backgroundStartPos", etc.

        // Additional string argument with original variable name is not a good solution too.
        // Because, I have similar "check" method that checks 4 connected position’s integers at once.
        // Therefore, 4 input ints with additional +4 string arguments will make a mess.
    }
}

长例：

void ShowMessage(string messageStr)
{

    // Problem: get original variable/argument name, as it was called, in the caller method.
    string callerMethodArgName;

    // If method was called from "Main" method, than callerMethodArgName should equal to "finishMsg".
    // If method was called from "DoWork" method, than callerMethodArgName should equal to "taskName".
    // If method was called from "StartProgram" method, than callerMethodArgName should equal to "startingMsg".    

    // …missing logic, reflection code, etc.

    // The next line is just a stub.
    callerMethodArgName = nameof(messageStr);

    Console.WriteLine($"Variable name is \"{callerMethodArgName}\"; value is \"{messageStr}\".");

}

void Main()
{
    StartProgram();
    DoWork("Programming…");

    // Example 1.
    string finishMsg = "Finish!";
    ShowMessage(finishMsg);
}

// Example, caller method 2.
void StartProgram()
{
    string startingMsg = "Starting program";
    ShowMessage(startingMsg);
}

// Example, caller method 3.
void DoWork(string taskName)
{
    ShowMessage(taskName);
}

当前节目输出：

// Variable name is "messageStr"; value is "Starting program".
// Variable name is "messageStr"; value is "Programming…".
// Variable name is "messageStr"; value is "Finish!".

必需/所需的输出：

// Variable name is "startingMsg"; value is "Starting program".
// Variable name is "taskName"; value is "Programming…".
// Variable name is "finishMsg"; value is "Finish!".

我不确定这是否可行。我花了几个小时玩反射，但不幸的是，它没有结果。在实际项目中进行调试时，这将非常方便。

Answer 1

您可以使用Linq.Expressions。首先，您需要更改--name-status的签名，如下所示：

--name-only

之后你可以这样称呼它：

CheckPosition

完整代码：

void CheckPosition(Expression<Func<int>> positionExpression)