php var_dump()函数
php var_dump 函数作用是判断一个变量的类型与长度,并输出变量的数值,如果变量有值输的是变量的值并回返数据类型.
来看看var_dump 语法:
var_dump ( var , var , bar);
下面来看看我刚才的一个实例吧.
php
$ta = 1 ;
$tb = ' t ' ;
echo var_dump ( $ta , $tb );
?>
输出为
int( 1 ) string ( 1 ) " t "
第一个为数字就是int(1)
简单吧,不过要注意一点,用var_dump里面的变量必须是存在的,如果变量存在但值是空的就会返回false;
PHP:var_dump()函数是干什么用的?
比如var_dump($get);是什么意思?
==========================================
此函数显示关于一个或多个表达式的结构信息,包括表达式的类型与值。

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