Javascript code:
function doSomething(v1,v2){ //blah; }
function SomeClass(callbackFunction,callbackFuncParameters(*Array*))={
this.callback = callbackFunction;
this.method = function(){
this.callback(parameters[0],parameters[1]) // *.*
}
}
var obj = new SomeClass( doSomething, Array('v1text','v2text') );
The problem is if I change function doSomething to
function doSomething(v1,v2,v3){ //blah; }
I have to change the corresponding line (marked as //*.*) in SomeClass to
this.callback(parameters[0],parameters[1],parameters[2]);
What can be done to avoid the (*.*) line to be changed no matter how the number of 'doSomething' function's parameters is changed?
Thanks a lot!
2 Answers
You probably want to use the apply method
this.callback.apply(this, parameters);
The first parameter to apply indicates the value of "this" within the callback and can be set to any value.
Another way now available is to use spread syntax.
this.callback(...callbackFuncParameters)
Here it is again with the full example from the OP:
function doSomething(v1,v2) {
console.log('doing', {v1, v2});
}
function SomeClass(callbackFunction, callbackFuncParameters) {
this.callback = callbackFunction;
this.method = function(){
this.callback(...callbackFuncParameters); // spread!
}
}
var obj = new SomeClass( doSomething, Array('v1text','v2text') );
obj.method()
// output: doing {v1: "v1text", v2: "v2text"}
