php 用户注册实例代码，适合初学者

php 用户注册实例代码，适合初学者

php教程 用户注册实例代码，适合初学者
  if($_POST[submit]){

   checkusername($_POST[username]);

    if($_SESSION["code"]==$_POST[code])

      {

    $username= str_replace(" ","",$_POST[username]);
    $password=md5($_POST[password].ALL_PS);
    $sql="INSERT INTO `member`.`user_list` (`uid`, `m_id`, `username`, `password`) VALUES (NULL, '$_POST[select]', '$username','$password' )";
    mysql教程_query($sql);
    echo "注册成功";
     }

    else
     {
      echo "验证码错误"."<br>";
      session_destroy();
     }
 }

   function checkusername($username)
          {
           $sql2 = "select uid from user_list where username='".mysql_escape_string($username)."'";
            $result = mysql_query($sql2) or die ('ERROR: '.mysql_error());
            if(mysql_num_rows($result)>0)
                {
                echo "该用户名已经存在，请更换！";

                exit();
                 }
            else{
                 echo "<script> location.href='reg.php'</script>";
                 }

           }

?>
<LINK href="common.css教程" type=text/css rel=stylesheet>

  <form action="" method="post">

  用户名：<input type="text" name="username" style="height:23px" /><br>
  密　码：<input type="password" name="password"  style="height:23px" /><br>
  职  位:

  <select name="select" size="1" style="height:23px" / >
    <option value="1">1</option>
    <option value="2">2</option>

  </select>
  <br/>

 

  验证码：<input type="code" name="code" size="10" style="height:23px" />
  <img src="imgcode.php">
  <br><br>
  <input type="submit" name="submit" value="注册"/>
  </form>