比较两个 PHP 变量时遇到问题
这似乎是一个愚蠢的问题，但它仍然困扰着我。我确信答案是一些小事。我认为这只是我长时间查看代码的情况之一。
我正在尝试比较两个 PHP 变量，看看它们是否相同。正如您在下面看到的，我将 $verification_answer 与 strrev(date("Ymd")) 进行比较，后者是今天的日期，颠倒过来。所以今天，$verification_answer 将为 31700102。但是，每次我尝试进行比较时，都会执行 if 语句（作为不匹配）。
$verification_answer = strrev(date("Ymd"));
if($verification != $verification_answer){
$failed .= "<h2>Attention:</h2><p>The verification code is incorrect. Please try again.</p>";
}
有人能看到这个问题吗？谢谢！
更新：$verification 来自 HTML 用户输入：
$verification = mysql_escape_string($_POST['verification']);
this may seem like a stupid question, but it is stumping me nontheless. I'm sure that the answer is something small. I think it's just one of those situations where I have been looking at the code for too long.
I am trying to compare two PHP variables to see if they are the same. As you can see below, I am comparing $verification_answer with strrev(date("Ymd")) which is today's date, reversed. So today, $verification_answer would be 31700102. Every time I try to do the comparison, however, the if statement executes (as a non-match).
$verification_answer = strrev(date("Ymd"));
if($verification != $verification_answer){
$failed .= "<h2>Attention:</h2><p>The verification code is incorrect. Please try again.</p>";
}
Can anyone see the issue? Thanks!
UPDATE: $verification is from HTML user input:
$verification = mysql_escape_string($_POST['verification']);
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如果这实际上是您想要做的，我认为您弄乱了第一行中的变量名称；应该是：
如果您不小心覆盖了
$verification_answer的值，并在未定义的情况下在比较中使用了$verification，则比较将始终为 false。 PHP 会发出警告，但如果禁用它们，您将看不到它If that's actually what you intended to do, I think you messed up the name of the variable in the first line; it should be:
If you accidentally overwrote the value of
$verification_answerand used$verificationin a comparison when it's undefined, the comparison will always be false. PHP will emit a warning, but if you have them disabled you won't see it我一定在某个地方拼写了验证错误...我将“验证”复制并粘贴到每个现有变量名称上，它解决了问题。谢谢！
I must have spelled verification wrong somewhere...I copy and pasted 'verification' over each existing variable name and it fixed the problem. Thanks!
if语句没有任何问题。显示这两个值，您应该会看到某种差异：也许
$verification不包含您认为它包含的内容，或者您之前拼写错误并分配给不同的变量，或者...There's nothing wrong with the
ifstatement. Display the two values and you should see some sort of difference:Perhaps
$verificationdoesn't contain what you think it does, or you misspelled it earlier and assigned to a different variable, or...