[表单] 转帖--限制输入框的长度(汉字解决方案) [复制链接]

电梯直达

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发表于 2005-12-23 19:39 |只看该作者 |倒序浏览

限制输入框的长度(汉字解决方案)
<script>
function getStringUTFLength(str) {
var value = str.replace(/[^x00-xff]/g," ");
return value.length;
}
function leftUTFString(str,len) {
if(getStringUTFLength(str)<=len)
return str;
var value = str.substring(0,len);
while(getStringUTFLength(value)>len) {
value = value.substring(0,value.length-1);
}
return value;
}
function count() {
var value = document.getElementById("licenseother").value;
value = value.replace(/[u4e00-u9fa5]/g," ");
//alert(value.length);
if(value.length>=255) {
with(window.event) {
cancelBubble = true;
keyCode=0;
returnValue = false;
}
document.getElementById("licenseother").value = leftUTFString(document.getElementById("licenseother").value,8);
}
document.getElementById("result").value = 255-getStringUTFLength(document.getElementById("licenseother").value);
}
</script>
<table width="100%">
<tr><td>
本输入框限制输入255个字符(汉字计算为2个字符：)
</td></tr>
<tr><td>
<textarea cols=80 rows=3 wrap="virtual" id="licenseother" onkeypress="count()" onkeyup="count()" onblur="count();" onChange="count();"></textarea>
</td></tr>
<tr><td>
剩余字符数：<input type="text" size="3" id="result" value="255">
</td></tr>
</table>
}