0 == 'ab' 好诡异的问题
PHP代码:
var_dump(0 == 'ab');
输出是true,为什马?我今天晕了么???????
回复内容:
PHP代码:
var_dump(0 == 'ab');
输出是true,为什马?我今天晕了么???????
请参考这个问题:php里,为什么0 == 'abc'是成立的?
比较一个整数和字符串,则字符串会被转换为整数
PHP手册上的原话。
http://www.php.net/manual/zh/language...
以字母或下划线开头的字符串,类型转换为整型时,转换为0.
你试试var_dump(0 == '1ab');输出什么
参考
http://php.jz123.cn/language.types.ty...
著名的PHP 2B之处:用==
进行判断,结果『可能』与你的预期相符。
在无法确定数据类型的前提下进行数据比对。建议使用===绝对等于来进行验证。不过要注意其他条件,比如,GET、POST、COOKIE等数据,都是string类型。
http://php.net/manual/zh/language.ope...
PHP.net有说明的.
这种情况必须使用===进行严格比较. 既比较类型,又比较值
PHP是一个弱类型的语言
请用===
来判断0 == "ab"

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