js实现的验证，学习用js控制td

<html> <head> <title>JS日积月累001 - rows 和 cells的使用</title> <script type="text/javascript"> function validForm(curForm, bodyName){ var bodyObj = document.getElementById(bodyName); var rowObj = null; var cellObj = null; if (bodyObj == null){ return false; } // 引用rows for (var i = 0; i < bodyObj.rows.length; i ++){ rowObj = bodyObj.rows[i]; // 带*的必须输入，引用cells if (rowObj.cells[0].innerText.indexOf("*") > 0){ if (rowObj.cells[1].childNodes[0].value == ""){ alert(rowObj.cells[0].innerText.replace(" * :", "") + "不能为空！"); return false; } } } alert("Pass validation"); //curForm.submit(); } </script> </head> <body> <form action="" method="post" name="loginFrm"> <table> <tbody id="validBody"> <tr> <td align="right">用户名 <font color="red">*</font> :</td> <td><input type="text" name="username" /></td> </tr> <tr> <td align="right">密码 <font color="red">*</font> :</td> <td><input type="password" name="username" /></td> </tr> <tr> <td align="right">子系统 <font color="red">*</font> :</td> <td> <select name="systemname"> <option value="">---请选择---</option> <option value="HR">人力资源系统</option> <option value="PUR">采购系统</option> <option value="SAL">销售系统</option> </select> </td> </tr> </tbody> <tbody> <tr> <td colspan="2"> <input type="button" value="提交" name="submit" onclick="validForm(this.form, 'validBody')"/> <input type="reset" value="Reset" name="reset"/> </td> </tr> </tbody> </table> </form> </body> </html>
[Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]