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JQuery setTimeout to pass error reporting for string parameters

  • 2020-03-30 03:19:51
  • OfStack
When you want to call some jQuery code to show a hidden element and call setTimeout() to set its HTML content after a delay:

The code for the entire page looks like this. 
 
<span style="font-size:18px;"><html> 
<head> 
<title></title> 
</head> 
<body> 
<a href="#" id='heihei' onclick="showNext('I am veinei ')">show next</a> 
<a href="#" id="log" style="display:none" >yes,I am the next </a> 
<script type="text/javascript" src="jquery-1.10.2.min.js"></script> 
<script type="text/javascript"> 
function showNext(text){ 
setTimeout("$('#log').show().text(text)",1000); 
} 
</script> 
</body> 
</html> 
</span>

The.show() call did succeed, but the.text() call failed.

I really don't have a better answer to this question... I wonder if jQuery made a change to the contents of this passed setTimeout() function that invalidated the variable.

I followed up with the next experiment. 
 
<span style="font-size:18px;"><html> 
<head> 
<title></title> 
</head> 
<body> 
<a href="#" id='heihei' onclick="showNext('I am veinei ')">show next</a> 
<a href="#" id="log" style="display:none" >yes,I am the next </a> 
<script type="text/javascript" src="jquery-1.10.2.min.js"></script> 
<script type="text/javascript"> 
function showNext(text){ 
setTimeout("alert(text)",1000); 
} 
</script> 
</body> 
</html> 
</span>

I'm going to see if jQuery is really the problem. I'm going to get the same error.

Then I found a book to read and found the problem.

When setTimeout() takes a string parameter, it executes globally, that is, outside of any function. 
 
<span style="font-size:18px;"><html> 
<head> 
<title></title> 
</head> 
<body> 
<a href="#" id='heihei' onclick="showNext('I am veinei ')">show next</a> 
<a href="#" id="log" style="display:none" >yes,I am the next </a> 
<script type="text/javascript" src="jquery-1.10.2.min.js"></script> 
<script type="text/javascript"> 
function showNext(text){ 
setTimeout(function(){$('#log').show().text(text);},1000); 
} 
</script> 
</body> 
</html> 
</span>

Solve the problem successfully.
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