How can i convert string to variable

I have a function in which i am receiving a string values .

Based on the value i want to create a variable.

Template<typename T>
void func( std::string str , T value )
{
    if( str == "int" )
     {
          int val = value;

     }

     if( str == "double" )
     {
          double val = value;

     }

    if( str == "string" )
     {
          std:string val = value;

     }    
}

is it possible to automate this function , instead of having lot of if conditions ?