Usage of the output Empty tag in the ThinkPHP template judgment

The empty tag of the ThinkPHP template is used to determine whether the template variable is null.

The empty tag of the ThinkPHP template is used to determine whether the template variable is null. Its function is equivalent to the empty () function in PHP. The empty label format is as follows:

<Empty name = "variable name"> content to be output </empty>

The usage is as follows:

<Empty name = "username"> username is null </empty

This example is equivalent:

<? Phpif (empty ($ username) {echo 'username is null ';}?>

If a non-null value is determined, the notempty label can be used as follows:

<Notempty name = "username"> username is not empty </notempty>

The two tags can be combined as follows:

<Empty name = "username"> username is null <else/> username is not empty </empty>