js limits the number of bytes that can be entered into the input box_form effects

The code is as follows: (Originally it was encapsulated based on the prototype, but it was found that the amount of code was completely increased, so it was changed back)

Thanks to sparks345 for raising the issue when pasting
In this case, we can only add a few more events onpropertychange, oninput, obj.watch("value",function(id,oval,nval){})
You can see here for details, tracking input value changes and compatible processing

<title>Limit the number of input bytes</title> <meta name="author" content="sohighthesky"> <style type="text/css"> #div1 {width:500px;margin:20px auto;} #div1 ul {list-style-type:decimal;line-height:25px;} </style> <div id="div1"> <ul> <li>Can enter 5 bytes: <input type="text" id="txt1" value="你好e"> </li> <li>Can enter 6 bytes: <input type="text" id="txt2" value="hello,"> </li> <li>Can enter 7 bytes: <input type="text" id="txt3" value="，he"> </li> <li>Can input n bytes: <input type="text" id="txt4"> </li> </ul> </div>
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Source: http:// www.cnblogs.com/sohighthesky/