Question

if ($fromcat == "true" || $fromcat == 1){

    error_log("binding to CAT " . $cat . " because pfc was " . $fromcat);   

} else {

    error_log("binding to ROOM " . $room . " because pfc was " . $fromcat); 

}

请查看上面的代码。

我想每个人都同意，如果$fromcat为0，我无法在控制台中获得“绑定到CAT（...）”消息。

然而，这是：

[01-Apr-2013 22:34:50] binding to CAT single because pfc was 0

怎么可能呢？您不能同时显示单词CAT和数字0！ PHP喝醉了吗？

Answer 1

使用相同的（===）比较运算符。

if ($fromcat === "true" || $fromcat === 1) {

    error_log("binding to CAT " . $cat . " because pfc was " . $fromcat);   

} else {

    error_log("binding to ROOM " . $room . " because pfc was " . $fromcat); 

}

您正在尝试将$fromcat与字符串"true"进行比较。如果你想将它与布尔值true进行比较，你可以使用$fromcat == true。否则：

如果您将数字与字符串进行比较或比较涉及数字字符串，则每个字符串都会转换为数字，并且数字会进行比较。

Documentation

Answer 2

逆转你的病情顺序也是一个好主意。

所以

if ($fromcat === "true" || $fromcat === 1)

变为

if ('true' === $fromcat || 1 === $fromcat)

原因：PHP - reversed order in if statement

if语句在PHP中没有得到尊重

2 个答案: