String- Function dictionary c# where functions have different arguments

Question

Basically I\'m trying to make a string to function dictionary in c#, I\'ve seen it done like this:

Dictionary>
<         


        

Answer 1

One possible approach to this problem is to create a wrapper class to your own dictionary that simply stores the function delegates as an object. You can then use generic methods to add a retrieve the function that match your signatures.

The following code example shows a very basic implementation:

class FunctionDictionary
{
    /// 

    /// Internal dictionary that will store the function delegates as Object.
    /// 
    private Dictionary m_Map = new Dictionary();

    /// 

    /// Add method to dictionary for specified key. Encapsulated method has no parameters.
    /// 
    public void Add(string key, Func function) 
    {
        m_Map.Add(key, function);
    }

    /// 

    /// Get method for specified key. Encapsulated method has no parameters.
    /// 
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }

    /// 

    /// Add method to dictionary for specified key. Encapsulated method has one parameters.
    /// 
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }

    /// 

    /// Get method for specified key. Encapsulated method has one parameters.
    /// 
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }


    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }
    public void Add(string key, Func function)
    {
        m_Map.Add(key, function);
    }


    public Object this[string key]
    {
        get
        {
            return m_Map[key];
        }
    }

    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }
    public Func Function(string key)
    {
        return (Func)m_Map[key];
    }

}

The following code example demonstrates the usage:

class FunctionMapUsage
{
    private FunctionDictionary functions = new FunctionDictionary();
    public string FunctionA()
    {
        return "A";
    }

    public string FunctionB(int value)
    {
        return value.ToString();
    }

    public int FunctionC(string str1, string str2)
    {
        return str1.Length + str2.Length;
    }

    public void CreateFunctionMap()
    {
        functions.Add("A", FunctionA);                      // Add Function A to map
        functions.Add("B", FunctionB);                 // Add Function B to map
        functions.Add("C", FunctionC);         // Add Function C to map
    }

    public void CallFunctions()
    {
        var functionA = functions.Function("A");                // Get Function A
        var functionB = functions.Function("B");           // Get Function B
        var functionC = functions.Function("C");   // Get Function C

        string resultA = functionA();
        string resultB = functionB(123);
        int resultC = functionC("parameter 1", "parameter 2");
    }
}

The CreateFunctionMap method simply adds new functions to the dictionary. The CallFunctions methods show how to extract and execute functions from the dictionary.