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form表单提交后提示 Undefined variable

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Jun 23, 2016 pm 01:26 PM

表单提交之后提示num_tries变量未定义，可是明明在第3行就定义了啊

回复讨论(解决方案)

第三行改一下：（int）强制类型转换的对象应该是$_POST吧。。。

$num_tries = (isset($_POST['num_tries'])) ? ((int)$_POST['num_tries']+1) : 1;

第 3 行应为
$num_tries = (isset($_POST['num_tries'])) ? $_POST['num_tries']+1 : 1;
不需要强制类型转换

+1之后确实不需要强制类型转换。。其实用(int)强转和intval()转换为数字不如直接+一个数

原来如此谢谢啦

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