城杆

<script language=javascript>
function onlyEng()
{
 if(!(event.keyCode>=65&&event.keyCode<=90))
   event.returnValue=false;
}
function onlyNum()
{
 if(!((event.keyCode>=48&&event.keyCode<=57)||(event.keyCode>=96&&event.keyCode<=105)))
//考虑小键盘上的数字键
   event.returnValue=false;
}
function isEmail(strEmail) {
if (strEmail.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
 return true;
else
 alert("wrong");
}
</script>
只能是汉字:<input onkeyup="value=value.replace(/[^\u4E00-\u9FA5]/g,'')"><br>
只能是英语字符:<input onkeydown="onlyEng();"><br>
只能是数字:<input onkeydown="onlyNum();"><br>
只能是英文字母和数字:<input onkeyup="value=value.replace(/[\W]/g,'') " onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\d]/g,''))"><br>
验证email格式:<input type=text onblur=isEmail(this.value)><br>
不能输入汉字<INPUT onpaste="return false;" style="IME-MODE: disabled; WIDTH: 400px" value="I only accept English input! Thanks for corporation!" name=textfield><br>