服务器控件TextBox，如何实现输入特定字符自动清空？

Question

我有个服务器控件<asp:TextBox ID="TextBox1" runat="server" Height="16px" Width="284px" ></asp:TextBox>并且还另外绑定了AutoCompleteExtender，我现在希望当用户在输入“上班”两字以后，文本框会自动清空文本框，请问如何实现？貌似js不支持服务器控件？

Answer 1

验证控件的话不是要通过一个button按钮激活验证控件以后才能执行操作吗？我想当输入以后离开文本框以后就清空

Answer 2

那么只能在客户端写javascript了啊，发一段给你参考一下吧，不是我写的，很久很久以前收藏的，不过也不复杂：<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>