在文本域中对输入字符及行数的限制-JavaScript教程-电脑教程之家
您正在看的JavaScript教程是:在文本域中对输入字符及行数的限制。
该特效，可以控制显示文本域中录入字符数与行数，请观看特效！
制作方法：
把如下代码加入<body>区域中：
<Script Language = "JavaScript">
<!--
function textCounter(theField,theCharCounter,theLineCounter,maxChars,maxLines,maxPerLine)
{
var strTemp = "";
var strLineCounter = 0;
var strCharCounter = 0;
for (var i = 0; i < theField.value.length; i++)
{
var strChar = theField.value.substring(i, i + 1);
if (strChar == '\n')
{
strTemp += strChar;
strCharCounter = 1;
strLineCounter += 1;
}
else if (strCharCounter == maxPerLine)
{
strTemp += '\n' + strChar;
strCharCounter = 1;
strLineCounter += 1;
}
else
{
strTemp += strChar;
strCharCounter ++;
}
}
theCharCounter.value = maxChars - strTemp.length;
theLineCounter.value = maxLines - strLineCounter;
}
//-->
</Script>
<form name="theForm" method="post" action="">
<textarea name="myText" cols="60" rows="10" wrap="VIRTUAL" onKeyUp="textCounter(theForm.myText,theForm.remChars,remLines,6000,165,100);"></textarea>
<br>剩余<input name=remChars type=text value="6000" size=3 maxlength=3 readonly>个输入字符
<br>剩余<input name=remLines type=text value="165" size=3 maxlength=3 readonly>输入行
</form>