Question

it may be a duplicate of

How to dynamically call a class' method in .NET?

and of

how to achieve calling a function dynamically, thats right the function to be called is decided from database values, using c#

but the above two have solutions which as the answers said are complicated, not for a beginner i guess.

and

both solutions contain “type” which from the code i think is for defining the class the method belongs to.

like

static void caller(String myclass, String mymethod)
    {
        // Get a type from the string 
        Type type = Type.GetType(myclass);
        // Create an instance of that type
        Object obj = Activator.CreateInstance(type);
        // Retrieve the method you are looking for
        MethodInfo methodInfo = type.GetMethod(mymethod);
        // Invoke the method on the instance we created above
        methodInfo.Invoke(obj, null);
    }

but my initial web site, only contains one class common to all the functions,

a database which has “function name” “func id”

supposed :- function name exactly same as that in code

i only want to achieve the following

• get the string value of function name according to the id mentioned in the text box

• now call that function, whose name is in the string variable

problem

the methodinfo, needs the “type.GetMethod(mymethod);”

..

Answer 1

In order to call a function you need to specify the type this function is declared on. If all functions you are going to call are declared on a common class you could do the following:

static void CallFunc(string mymethod)
{
    // Get a type from the string 
    Type type = typeof(TypeThatContainsCommonFunctions);

    // Create an instance of that type
    object obj = Activator.CreateInstance(type);

    // Retrieve the method you are looking for
    MethodInfo methodInfo = type.GetMethod(mymethod);

    // Invoke the method on the instance we created above
    methodInfo.Invoke(obj, null);
}

If the functions you are going to call are static you don’t need an instance of the type:

static void CallFunc(string mymethod)
{
    // Get a type from the string 
    Type type = typeof(TypeThatContainsCommonFunctions);

    // Retrieve the method you are looking for
    MethodInfo methodInfo = type.GetMethod(mymethod);

    // Invoke the method on the type
    methodInfo.Invoke(null, null);
}