PHP中false和true问题
举个例子
var_dump(true == -1);//true
PHP中的true和false到底对应的个啥?
回复内容:
举个例子
var_dump(true == -1);//true
PHP中的true和false到底对应的个啥?
我感觉这个问题你可以看看手册
给了和详细的说明
在PHP中任何类型的值, 与bool比较都会被转化成bool比较
当转换为 boolean 时,以下值被认为是 FALSE:
布尔值 FALSE 本身
整型值 0(零)
浮点型值 0.0(零)
空字符串,以及字符串 "0"
不包括任何元素的数组
不包括任何成员变量的对象(仅 PHP 4.0 适用)
特殊类型 NULL(包括尚未赋值的变量)
从空标记生成的 SimpleXML 对象
如果有不对的地方还请谅解
你可以百度一下“PHP的类型转换规则”:
整型 转 布尔型 情况下
0 转换为 FALSE ,非零的其他整型数字转换为 TRUE
false == 0
true == !false == !0
http://php.net/manual/zh/language.types.boolean.php
瞅瞅

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