Method for obtaining external function names using JS scripts (Appendix: Code)

The method is saved in the class variable, and can be obtained through the class variable when needed.
Generally, If we generate an instance
For example, var temp = new TopnetTree ();
If we pass in a method by setting attributes, we will find that the content of a function is passed in, not the function name.
For example, temp. fileAction = fnTest; // fnTest is a function.
So I wrote a method to implement this function.
Determine the input content through arguments:
Implement the following functions:
The input content is blank and NO content is executed.
Input a parameter to indicate a function without Parameters
If multiple parameters are input, the first parameter is used as the function name, followed by each parameter.

Reference content is as follows: TopnetTree. prototype. setFileAction = function (){ Var fnName, fnArgs = ""; If (arguments. length = 0 ){ Return 0; } Else if (arguments. length = 1 ){ FnName = arguments [0]; } Else { FnName = arguments [0]; For (var I = 1; I <arguments. length; I ++ ){ FnArgs + = "," + arguments [I]; } FnArgs = fnArgs. replace (",",""); }   This. fileAction = fnName + "(" + fnArgs + ")"; }