Question

我有一个简单的测试页面，用于确认GET值

<?php
if ($_GET ['car'] = 'yes') {
echo 'You have a car. It is set to: ' . $_GET ['car'] . '<br>';
}
if ($_GET ['boat'] = 'yes') {
echo 'You have a boat. It is set to: ' . $_GET ['boat'] . '<br>';
}
?>

我正在验证多个网址字符串：

test.php？car = yes＆amp; boat = no
test.php的汽车=否安培;舟=无
test.php的汽车=否安培;舟=是
test.php的汽车= YES＆安培;舟=是

如果我导航到URL“test.php？car = no＆amp; boat = no”，echo函数将打印“yes”而不是“no”。

请帮助我理解为什么我没有收到'否'而不是'是'的预期结果。谢谢。

Answer 1

你的if语句使$ _GET [＆＃39; car＆＃39;]等于＆＃39;是＆＃39;而不是检查IF $ _GET [＆＃39; car＆＃39;] IS等于＆＃39;是＆＃39;。试试这个：

<?php
    if ($_GET['car'] == 'yes') {
        echo 'You have a car. It is set to: ' . $_GET['car'] . '<br>';
    }
    if ($_GET['boat'] == 'yes') {
        echo 'You have a boat. It is set to: ' . $_GET['boat'] . '<br>';
    }
?>

Answer 2

作业运算符

$a=$b

基本赋值运算符是＆＃34; =＆＃34;。 as＆＃34;等于＆＃34;。唐＆＃39;吨。这实际上意味着左操作数被设置为右侧表达式的值（即＆＃34;设置为＆＃34;）。

比较运算符

$a == $b 

Results TRUE, if $a is equal to $b after type juggling.

因此，将代码更改为以下代码，以便在未分配时进行比较。

<?php
if ($_GET ['car'] == 'yes') {
echo 'You have a car. It is set to: ' . $_GET ['car'] . '<br>';
}
if ($_GET ['boat'] == 'yes') {
echo 'You have a boat. It is set to: ' . $_GET ['boat'] . '<br>';
}
?>

php获取返回未分配的值

2 个答案: