function.php

一个小型图书管理系统

<?
//######################定义函数checkuser()##########################
function checkuser(){
global $user_name,$user_card,$user_pass,$user_repass,$user_email,$user_ques,$user_answ;
global $hostname,$dbuser,$dbname,$dbpassword,$book_table,$send_table,$user_table;
if(empty($user_name)){echo "用户名不能为空。";
echo "<a href=\"javascript:history.back();\">点此返回</a>";
exit;}
if(empty($user_card)){
echo "<a href=\"javascript:history.back();\">请输入你的借阅证号</a>";
exit;
}
if(strlen($user_card)<>'8'){
	echo"你输入的借阅证号码位数不对。";
	echo "<a href=\"javascript:history.back();\">点此返回</a>";
exit;
}
if(empty($user_pass)){
  echo "你的密码呢？";
	echo "<a href=\"javascript:history.back();\">点此返回</a>";
	exit;
}
if(empty($user_repass)||(strcmp($user_pass,$user_repass))){
	echo "你的确认密码有误";
	echo "<a href=\"javascript:history.back();\">点此返回</a>";
	exit;
}
if(empty($user_email)){
  echo "你的E-MAIL不能为空。";
  echo "<a href=\"javascript:history.back();\">点此返回</a>";
    exit;
	}
	if(!eregi("^[_\.0-9a-z-]+@([0-9a-z][0-9a-z-]+\.)+[a-z]{2,3}$",$user_email)){
	echo "你的E-MAIL格式不对。";
	echo "<a href=\"javascript:history.back();\">点此返回</a>";
    exit;
	}
$db=mysql_connect($hostname,$dbuser,$dbpassword) or die("数据库连接错误！");
  mysql_select_db($dbname,$db);
$sql="select*from $user_table where user_name='".$user_name."'";
$result=mysql_query($sql,$db);
if(mysql_fetch_object($result))
{
    echo"已经有相同的名字存在，请<a href=register.php>重新填写</a>";
	exit;
}
$query=mysql_query("insert into $user_table values('','$user_name','$user_card','$user_pass','$user_email','$user_ques','$user_answ')") or die("数据表连接错误。");
   if($query){
    echo $user_name.",感谢你的注册，如果此页面没有自动返回，请点击此处<a href='index.php'>返回</a>登录";
	echo "<meta http-equiv=\"refresh\" content=\"0;url=index.php\"></meta>";
 }
 }
?>