文档介绍：<!DOCTYPEhtmlPUBLIC"-//W3C////EN"""><html><head><title>用户注册!</title><style>ul{list-style-type:none;}ulli{margin-bottom:15px;}.front_input{width:150px;display:block;text-align:right;}.front_input,ulliinput{float:left;}.after_input{margin-left:5px;color:#FF0000;font-size:14px;folat:left;}ulinput{width:200px;height:18px;}.front_input{clear:both;}</style><scripttype="text/javascript">//保存一个密码用于校验var_pass;/***检查用户名*/=function(){(/(^\s*)|(\s*$)/g,"");}//---------------------------------------------------------------------------functioncheck_username(){varusername;username=('username').value;username=();if(username==""){('username_error').innerHTML="请输入用户名";}else{if(/^\w{6,20}$/.test(username)){('username_error').innerHTML="";}else{('username_error').innerHTML="请输入6~20字符【0-9】【a-z-A-Z】";}}}/***检查密码*///---------------------------------------------------------------------------functioncheck_pass(){varpass;pass=('pass').value;pass=();_pass=pass;if(pass==""){('pass_error').innerHTML="请输入密码";}else{if(/^\w{6,20}$/.test(pass)){('pass_error').innerHTML="";}else{('pass_error').innerHTML="请输入6~20字符【0-9】【a-z-A-Z】";}   }}/***检查Email*/