Including jQuery causes standard JavaScript to stop functioning?

I'm getting started with jQuery. I'v been trying to mix it with some of my preexisting JavaScript code so I don't have to rewrite everything. I have read many places that this is totally doable. However, whenever i include any lines of jQuery the standard JavaScript stops functioning.

Here's a few examples:

<!DOCTYPE html> <html> <head> <style> #testjquery { height: 300px; width: 300px; } </style> </head> <body> <div id="testjquery" onclick="testClick()">This is the stuff.</div> <script src='jquery-1.10.2.min.js'></script> <script> $(document).ready(function() { function testClick() { document.getElementById("testjquery").style.background = "blue"; } }); </script> </body> </html>

This doesn't work, and when clicks I get a function not defined error.

But, putting this in the body

<body> <div id="testjquery">This is the stuff.</div> <script src='jquery-1.10.2.min.js'></script> <script> $(document).ready(function() { $("#testjquery").click(function() { $(this).css("background", "blue"); }); }); </script> </body>

Works fine, as does the equivalent in standard JavaScript.


Don't wrap your function in DOM ready($(document).ready(function(){) handler.As it is a anonymous function so your testClick() function has local scope.So you can not call it outside the DOM ready

function testClick() { document.getElementById("testjquery").style.background = "blue"; }

Read What is the scope of variables in JavaScript?


The following block is run when the document is ready, and creates a local function testClick() that is not visible outside of the anonymous function (the one created by function(){ on the first line).

$(document).ready(function(){ function testClick(){ document.getElementById("testjquery").style.background="blue"; } });

If you want to define a global function that can be called directly, you shouldn't put it inside a document ready handler. Change it to this instead.

function testClick(){ document.getElementById("testjquery").style.background="blue"; }


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