html怎么验证表单 一段表单JS验证代码

一段表单JS验证代码  

　　<script Language= JavaScript >function FormCheck(theform){if (theform hybz value == ){alert( 请选择注册类别！ );theform hybz focus();return (false);}if (theform user value == ){alert( 请填写您的用户名！ );theform user focus();return false;}var filter=/^\s*[ A Za z _ ]{ }\s*$/;if (!filter test(theform user value)) {alert( 用户名填写不正确 请重新填写！可使用的字符为（A Z a z _ )长度不小于 个字符 不超过 个字符 注意不要使用空格 );theform user focus();theform user select();return false;}if (theform pass value == ){alert( 请填写您的密码！ );theform pass focus();return false;}if(nfirmPassword value== ){alert( 请输入您的确认密码！ );nfirmPassword focus();return false;}var filter=/^\s*[ A Za z _ ]{ }\s*$/;if (!filter test(theform pass value)) {alert( 密码填写不正确 请重新填写！可使用的字符为（A Z a z _ )长度不小于 个字符 不超过 个字符 注意不要使用空格 );theform pass focus();theform pass select();return false;}if (theform pass value!=nfirmPassword value ){alert( 两次填写的密码不一致 请重新填写！ );theform pass focus();theform pass select();return false;}if (theform question value == ){alert( 请输入密码提示问题！ );theform question focus();return (false);}if (theform answer value == ){alert( 请输入密码提示答案！ );theform answer focus();return (false);}if (theform name value == ){alert( 请输入您的姓名！ );theform name focus();return (false);}if (theform sf value == ){alert( 请选择区域！ );theform sf focus();return (false);}if (theform city value == ){alert( 请选择城镇名！ );theform city focus();return (false);}if (theform qymc value == ){alert( 请输入您的公司名称！ );theform qymc focus();return (false);}if (theform qylb value == ){alert( 请选择您的单位性质！ );theform qylb focus();return (false);}if (theform address value == ){alert( 请输入您的联系地址！ );theform address focus();return (false);}if (theform post value == ){alert( 请输入邮政编码！ );theform post focus();return (false);}if (theform phone value == ){alert( 请输入您的联系电话！ );theform phone focus();return (false);}if (theform email value == ){alert( 请输入您的电子邮件地址！ );theform email focus();theform email select();return false;}var filter=/@/;if (!filter test(theform email value)) {alert( 邮件地址不正确 请重新填写！ );theform email focus();theform email select();return false;}<! theform submit() >}</script>

　　调用代码 表单提交时用下列代码调用