为什么我写的js代码没有起作用

用户名：" id="username" class="input-text1"/>

密码：" id="pwd" class="input-text1"/>

确认密码：" id="repwd" class="input-text1"/>

邮箱：" id="email" class="input-text1"/>

性别：男
     女

QQ：" id="QQ" class="input-text1"/>

个人主页：" id="homepage" class="input-text1"/>

生日：" id="birth" class="input-text1"/>

现住城市：" id="city" class="input-text1"/>

家庭住址：" id="adr" class="input-text1"/>

 

/*-------省略部分代码---------*/
<script> <br /> String.prototype.trim = function() {return this.replace(/^\s+|\s+$/g, '');} <br /> function do_submit() { <br /> var username = document.getElementById('username'); <br /> if ( username.value.trim() == '' ) { <br /> window.alert('用户名尚未填写。'); <br /> username.className = 'input-error'; //设置CSS样式 <br /> username.focus(); //聚焦 <br /> username.value = ''; <br /> return false; //阻止表单提交 <br /> } <br /> <br /> var pwd = document.getElementById('pwd'); <br /> if ( pwd.value.trim() == '' ) { <br /> window.alert('密码尚未填写。'); <br /> pwd.className = 'input-error'; <br /> pwd.focus(); <br /> pwd.value = ''; <br /> return false; <br /> } <br /> //window.alert(passwd.value.trim().length); <br /> if ( pwd.value.trim().length < 6 ) { <br /> window.alert('密码不能少于六位！'); <br /> pwd.className = 'input-error'; <br /> pwd.focus(); <br /> pwd.value = ''; <br /> return false; <br /> } <br /> <br /> var repwd = document.getElementById('repwd'); <br /> if ( repwd.value.trim() == '' ) { <br /> window.alert('重复密码尚未填写。'); <br /> repwd.className = 'input-error'; <br /> repwd.focus(); <br /> repwd.value = ''; <br /> return false; <br /> } else { <br /> if ( pwd.value.trim() != repwd.value.trim() ) { <br /> window.alert('两次密码不一致！'); <br /> return false; <br /> } <br /> } <br /> <br /> var email = document.getElementById('email'); <br /> if ( email.value.trim() == '' ) { <br /> window.alert('电子邮件尚未填写。'); <br /> email.className = 'input-error'; <br /> email.focus(); <br /> email.value = ''; <br /> return false; <br /> } <br /> </script>

回复讨论(解决方案)

==》

 结尾少个}