<script>
 function regInput(obj, reg, inputStr)
 {
  var docSel = document.selection.createRange()
  if (docSel.parentElement().tagName != "INPUT") return false
  oSel = docSel.duplicate()
  oSel.text = ""
  var srcRange = obj.createTextRange()
  oSel.setEndPoint("StartToStart", srcRange)
  var str = oSel.text + inputStr + srcRange.text.substr(oSel.text.length)
  return reg.test(str)
 }
</script>

小写英文：<xmp style= "display:inline"> </xmp>
<input onkeypress= "return regInput(this,/^[a-z]*$/,String.fromCharCode(event.keyCode))"
  onpaste = "return regInput(this,/^[a-z]*$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^[a-z]*$/,event.dataTransfer.getData('Text'))"
  style="ime-mode:Disabled"
><br>

大写英文：<xmp style= "display:inline"> </xmp>
<input onkeypress= "return regInput(this,/^[A-Z]*$/,String.fromCharCode(event.keyCode))"
  onpaste = "return regInput(this,/^[A-Z]*$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^[A-Z]*$/,event.dataTransfer.getData('Text'))"
  style="ime-mode:Disabled">
<br>

任意数字：<xmp style="display:inline"> </xmp>
<input onkeypress= "return regInput(this,/^[0-9]*$/,String.fromCharCode(event.keyCode))"
  onpaste = "return regInput(this,/^[0-9]*$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^[0-9]*$/,event.dataTransfer.getData('Text'))"
  style="ime-mode:Disabled"
><br>

限2位小数：<xmp style="display:inline"> </xmp>
<input onkeypress= "return regInput(this,/^\d*\.?\d{0,2}$/,String.fromCharCode(event.keyCode))"
  onpaste = "return regInput(this,/^\d*\.?\d{0,2}$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^\d*\.?\d{0,2}$/,event.dataTransfer.getData('Text'))"
  style="ime-mode:Disabled"
> 如: 123.12<br>

日　　期：<xmp style="display:inline"> </xmp>
<input onkeypress= "return regInput(this,/^\d{1,4}([-\/](\d{1,2}([-\/](\d{1,2})?)?)?)?$/,String.fromCharCode(event.keyCode))"
  onpaste = "return regInput(this,/^\d{1,4}([-\/](\d{1,2}([-\/](\d{1,2})?)?)?)?$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^\d{1,4}([-\/](\d{1,2}([-\/](\d{1,2})?)?)?)?$/,event.dataTransfer.getData('Text'))"
  style="ime-mode:Disabled"
> 如: 2002-9-29<br>

任意中文：<xmp style="display:inline"> </xmp>
<input onkeypress= "return regInput(this,/^$/,String.fromCharCode(event.keyCode))"
  onpaste = "return regInput(this,/^[\u4E00-\u9FA5]*$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^[\u4E00-\u9FA5]*$/,event.dataTransfer.getData('Text'))"
><br>

部分英文：<xmp style="display:inline"> </xmp>
<input onkeypress= "return regInput(this,/^[a-e]*$/,String.fromCharCode(event.keyCode))"
  onpaste = "return regInput(this,/^[a-e]*$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^[a-e]*$/,event.dataTransfer.getData('Text'))"
  style="ime-mode:Disabled"
> 范围: a,b,c,d,e<br>

部分中文：<xmp style="display:inline"> </xmp>

<script language=javascript>
function checkChinese(oldLength, obj)
{
 var oTR = window.document.selection.createRange()
 var reg = /[^一二三四五六七八九十]/g
 oTR.moveStart("character", -1*(obj.value.length-oldLength))
 oTR.text = oTR.text.replace(reg, "")
}
</script>
<input onkeypress="return false" onkeydown="setTimeout('checkChinese('+this.value.length+','+this.uniqueID+')', 1)"
  onpaste = "return regInput(this,/^[一二三四五六七八九十]*$/,window.clipboardData.getData('Text'))"
  ondrop = "return regInput(this,/^[一二三四五六七八九十]*$/,event.dataTransfer.getData('Text'))"
> 范围: 一二三四五六七八九十<br>