javascript 输入框字符数提示,超出提示 猛击这里看demo
<!————代码开始———–><div><input type=”text” id=”in” onkeyup=”tslx(this);” size=”100″ /><br /><i id=”alt”></i></div><script type=”text/javascript”>function len(s) {var l = 0;var a = s.split(“”);
for (var i=0;i<a.length;i++) {if (a[i].charCodeAt(0)<299) {l++;} else {l+=2;}}return l;}function tslx(t,tl){/*t = input thistl = 字符限制数; 默认 50个字符 25个汉字*/tl = tl || 50;var v = t.value;var txt = “已经输入” + len(v) + “字符”;if( len(v) > tl){txt += “,超出” + (len(v) – tl) + “字符”;document.getElementById(“alt”).style.color = “red”;}else{txt += “,还能输入” + (tl – len(v)) + “字符”;document.getElementById(“alt”).style.color = “”}document.getElementById(“alt”).innerHTML = txt;}</script>