js验证表单大全

js验证表单大全
 1. 长度限制
 <script>
 function test() 
{
 if(document.a.b.value.length>50)
 {
 alert("不能超过50个字符！");
 document.a.b.focus();
 return false;
 }
 }
 </script>
 <form name=a>
 <textarea name="b" cols="40" wrap="VIRTUAL" rows="6"></textarea>
 <input type="submit" name="Submit" value="check">
 </form> 
2. 只能是汉字 
<input/oblog/value.replace(/[^\u4E00-\u9FA5]/g,'')">
 3." 只能是英文
 <script language=javascript>
 function onlyEng()
 {
 if(!(event.keyCode>=65&&event.keyCode<=90))
 event.returnvalue=false;
 }
 </script>
 <input>
 4. 只能是数字
 <script language=javascript>
 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;
 }
 </script>
 <input>
 5. 只能是英文字符和数字
 <input/oblog/value.replace(/[\W]/g,"'') "onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\d]/g,''))">
 6. 验证油箱格式
 <SCRIPT LANGUAGE=javascript RUNAT=Server>
 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("oh");
 }
 </SCRIPT>
 <input type=text onblur=isEmail(this.value)>
 7. 屏蔽关键字(这里屏蔽***和****)
 <script language="javascript1.2">
 function test() {
 if((a.b.value.indexOf ("***") == 0)||(a.b.value.indexOf ("****") == 0)){
 alert("");
 a.b.focus();
 return false;}
 }
 </script>
 <form name=a>
 <input type=text name=b>
 <input type="submit" name="Submit" value="check">
 </form>
 8. 两次输入密码是否相同
 <FORM METHOD=POST ACTION="">
 <input type="password" id="input1">
 <input type="password" id="input2">
 <input type="button" value="test">
 </FORM>
 <script>
 function check()
 { 
with(document.all){
 if(input1.value!=input2.value)
 {
 alert("false")
 input1.value = "";
 input2.value = "";
 }
 else document.forms[0].submit();
 }
 }
 </script>
 路政管理系统应用：
 //非空验证
 function checkoname(){
 var casename= document.all['caseInfo.casename'].value;
 if(casename==""){
   alert("案由不能为空！请输入执法机构");
   casename.focus();
   return false;
 }
   return true;
 }
 //机构简称非空验证
 function checkcpunishbase(){
 var cpunishbase=document.all['caseInfo.cpunishbase'].value;
 if(cpunishbase==""){
   alert("处罚依据不能为空！请输入机构简称");
   cpunishbase.focus();
   return false;
 }
   return true;
 }