循环直到用 PHP 返回 true
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Loop until returned true with PHP
提问by DannyF247
I'm generating a random code, and I need to check to be sure that the code isn't already in the database. I'm assuming this requires some type of a loop. I have my query all setup and I need it to run a block of code again if mysql_num_rows == 0.
我正在生成一个随机代码，我需要检查以确保该代码不在数据库中。我假设这需要某种类型的循环。我的查询全部设置完毕，如果mysql_num_rows == 0.
回答by Blender
Use a do...whileloop:
使用do...while循环：
do {
// Your logic
} while (condition);
回答by James L.
$key = true;
while($key){
// Do stuff
if(mysql_num_rows($result) > 0) $key = false;
}
回答by Martin Macak
Simple upgrade of James L. script - loop script for test if exist login ID in database. If exist, will add +1 after login:
James L. 脚本的简单升级 - 用于测试数据库中是否存在登录 ID 的循环脚本。如果存在，登录后会加+1：
$key = true;
$a = 1;
$login_test_origin=$login_test;
while($key){
$query_test="SELECT count(*) as 'all' FROM user WHERE login='$login_test'";
$row_test=mysql_fetch_array(mysql_query($query_test));
$error=$row_test[all];
if($error > 0) {
$key = true;
$login_test=$login_test_origin.$a;
$a++;
}
else {
$key = false;
$login=$login_test;
}
}
echo"Used login ID: $login";
回答by AMB
Here is a quite different route:
这是一条完全不同的路线：
while(true){
if(/* Your logic which you expect to be true */){
break;
}
}
