7

How can I get the name of the first method called from an expression in C#? Something like the fictional MethodUtils.NameFromExpression() below:

Expression<Action<string>> expr = s => s.Trim();
Assert.AreEqual("Trim", MethodUtils.NameFromExpression(expr));

Ideally any util method would be written/overloaded in such a way that it could take expressions for any of the Action or Func delegate types.

Thanks in advance.

UPDATE

I found an answer (below) but would still like input as to whether this is a good solution or whether there already exists a way of doing this in the BCL.

chillitom
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  • Check my answer at http://stackoverflow.com/questions/9412182/get-the-names-of-interface-methods-strong-typed/32245698#32245698 HTH.. – ShloEmi Aug 27 '15 at 13:27

1 Answers1

11

A bit of digging with the debugger and I've answered my own question:

public static class MethodUtils
{
    public static string NameFromExpression(LambdaExpression expression)
    {
        MethodCallExpression callExpression = 
            expression.Body as MethodCallExpression;

        if(callExpression == null)
        {                
            throw new Exception("expression must be a MethodCallExpression");
        }

        return callExpression.Method.Name;
    }
}

Any comments on this implementation?

casperOne
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chillitom
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  • Exactly what I was about to suggest! – LukeH Feb 12 '10 at 15:40
  • "Any comments on this implementation?" ==> Check my answer at http://stackoverflow.com/questions/9412182/get-the-names-of-interface-methods-strong-typed/32245698#32245698 – ShloEmi Aug 27 '15 at 13:29