C# Generics and Type Checking

Question

I have a method that uses an IList<T> as a parameter. I need to check what the type of that T object is and do something based on it. I was trying to use the T value, but the compiler does not not allow it. My solution is the following:

private static string BuildClause<T>(IList<T> clause) {     if (clause.Count > 0)     {         if (clause[0] is int || clause[0] is decimal)         {            //do something         }         else if (clause[0] is String)         {            //do something else         }         else if (...) //etc for all the types         else         {            throw new ApplicationException("Invalid type");         }     }  } 

There has to be a better way to do this. Is there some way I can check the type of T that is passed in and then use a switch statement?

Answer 1

You could use overloads:

public static string BuildClause(List<string> l){...}  public static string BuildClause(List<int> l){...}  public static string BuildClause<T>(List<T> l){...} 

Or you could inspect the type of the generic parameter:

Type listType = typeof(T); if(listType == typeof(int)){...}