Question

I’m trying to build some objects to make my life a bit easier, but somehow I can’t get it working. I got the following code:

function Paragraph(className, innerHTML, parentId) {
    this.className = className;
    this.innerHTML = innerHTML;
    this.parentId = parentId;
}

Paragraph.generateParagraph = function() {  
    console.debug(this.parentId); // Expect 'testDiv'
    alert(this.parentId);   // Expect 'testDiv'
};

function initialize() {
    var paragraph = new Paragraph('testClass', 'testTitle', 'testDiv');
    paragraph.generateParagraph;
}

window.onload = initialize;

When I try to execute this code nothing happens. I expect the console.debug and alert in the generateParagraph method to be executed.

Any help would be appreciated!

Answer 1

Add methods to the constructor’s prototype, not the constructor itself.

function Paragraph(className, innerHTML, parentId) {
    this.className = className;
    this.innerHTML = innerHTML;
    this.parentId = parentId;
}

Paragraph.prototype.generateParagraph = function() {  
    console.debug(this.parentId);  // Expect 'testDiv'
    alert(this.parentId);   // Expect 'testDiv'
};

function initialize() {
    var paragraph = new Paragraph('testClass', 'testTitle', 'testDiv');
    paragraph.generateParagraph();
}

window.onload = initialize;