php提交表单时判断 if($_POST[submit])与 if(isset($_POST[submit])) 的区别
应该这样用if(isset($_POST['submit'])) {
}
提交表单时 if($_POST[submit])与 if(isset($_POST[submit])) 的区别
第一种方法会出现一个warning，第二种相对更严谨。
还有就是POST的键名最好加上单引号，这样效率稍微高点（大概3-4倍）。
恩 差不多那个意思，如果设置了这个变量则返回true
PHP中if(isset($_POST['Submit']))是什么意思
isset -- 检测变量是否设置
判断post过来的数据是否被提交过来
复制代码 代码如下:
if(isset($_POST["submit"]){
echo "提交过来了";
}else
{
echo "submit is no come~";
}
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