使用json_encode方法将PHP数组传递到外部Javascript函数中，结果为“未定义”

Question

I have searched for that, i got some ideas from following site also. Passing PHP array into external Javascript function as array My sample code is below:

 <?php $array_sample = array("c1","c2"); $newArray = json_encode($array_sample); ?>
 <INPUT type="button" value="Php Array" onclick="Test(<?php echo $newArray ?>)" />
 <script language="javascript"> function Test(test_arr){    alert(test_arr); }</script>

For above code, I am getting undefined as alert message . Any Help would be appreciated.

Answer 1

When you use json_encode() , double-quotes are preserved in the result. So, json_encode($array_sample) produces:

["c1","c2"]

When this is put into your HTML, you have:

<INPUT type="button" value="Php Array" onclick="Test(["c1","c2"])" />

If you can tell, the double-quotes from your json-output break the HTML which break what's passed to the Test() method.

To fix this, you could use htmlentities() to convert the double-quotes to HTML-values " :

<INPUT type="button" value="Php Array" onclick="Test(<?php echo htmlentities($newArray) ?>)" />

EDIT ( htmlentities() vs. addslashes() )
It appears that using addslashes() actually won't work because an escaped double-quote in an attribute, such as onclick="Test(\\"value\\")" is invalid. However, an html-entity version such as onclick="Test("value")" works.

Because of this, I have changed my original answer from "use addslashes() " to "use htmlentities() ").