Class Function Call

Question

I have a class setup as follows:

var oTest = new TEST();
function TEST() {
 this.String = function(sString) {
 this.Trim = function() {
 }
 }
}

I want to be able to call the Trim function as follows:

var sTrimmed = oTest.String(" something").Trim();

Is this the correct approach? Any help would be greatly appreciated as i have never done functions inside class functions before.

Answer 1

Add your methods to the prototype of the constructor function, and do return this; in String, to return the same object, which makes it chainable.

var oTest = new TEST();
function TEST() {}
TEST.prototype.String = function(aString) {
 this.the_string = aString;
 return this;
};
TEST.prototype.Trim = function() {
 this.the_string = this.the_string.trim();
 return this;
};
TEST.prototype.getString = function() {
 return this.the_string;
};
var sTrimmed = oTest.String(" something")
 .Trim()
 .getString();

live demo: http://jsfiddle.net/BcwgC/