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; }