Uncaught TypeError: onClick is not a function code example

Example 1: Uncaught ReferenceError: function is not defined at HTMLUnknownElement.onclick

//Your program can't find the function so do this.

//You can assign the button onclick as an id.
//then attach an eventListener on run time like this:

<button id="btn">Click me!</button>

var btn = document.getElementById("btn");
btn.addEventListener("click", function() {
	//Do something here
}, false);

Example 2: Uncaught TypeError is not a function JavaScript

jQuery(document).ready(function($){

    // jQuery code is in here

});