Javascript code _ javascript skills

The javascript code is used to calculate the remaining length of the text field. This Code is also a simple implementation method.

Remaining words in the text field calculated by JS <textarea cols = "20" rows = "4" onkeyup = "displaySpareNumber (this, 10)" onchange = "displaySpareNumber (this, 10) "> </textarea> <script type =" text/javascript "language =" JavaScript "> function displaySpareNumber (_ this, size) {var spareNumber = document. getElementById ("spareNumber"); // Chinese Character length var len = _ this. value. replace (/[^ \ x00-\ xff]/gi, 'xx '). length; var snum = parseInt (size)-len; spareNumber. value = snum; If (snum <0) {if (_ this. value. length! = Len) {if (len-_ this. value. length)> (size/2) {_ this. value = _ this. value. substring (0, size/2);} else {_ this. value = _ this. value. substring (0, size-(len-_ this. value. length) ;}} else {_ this. value = _ this. value. substring (0, size);} spareNumber. value = 0; return ;}} <input id = "spareNumber" name = "spareNumber" value = "10" size = "1"/> <br> note: <br> displaySpareNumber (this, 10) <br> and <br> <input id = "spareNumber" name = "spareNumber" value = "10" size = "1"/> <br> You define 10 content Length.
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