php 检查 Laravel 视图中是否为 null 和空字符串
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Check if null and empty string in Laravel view
提问by i-faith
in my view I have to output separately the one that is nulland the one that is empty string
在我看来，我必须分别输出那个null和那个empty string
so i have this:
所以我有这个：
@if( $str->a == null)
... // do somethin
@endif
@if( $str->a == '')
... // do somethin
@endif
the problem is they the same result.
问题是它们的结果相同。
Thanks
谢谢
回答by Alexey Mezenin
回答by Krishna Jonnalagadda
@if( !empty($str->a))
... // do somethin
@endif
This are consider for empty
这是考虑为空
The following things are considered to be empty:
以下内容被认为是空的：
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array() (an empty array)
$var; (a variable declared, but without a value)
回答by Hiren Pipariya
You can try this
你可以试试这个
@isset($str->a)
// $str->a is defined and is not null...
@endisset
@empty($str->a)
// $str->a is "empty"...
@endempty
回答by Jim Wright
$str->acan't be null and ''at the same time. Have you tried @elseif?
$str->a不能同时为空''。你试过@elseif吗？
@if( is_null($str->a))
... // do somethin
@elseif( $str->a == '')
... // do somethin
@endif
actually, it should only shows the ones that is null and not the one that is empty.
实际上，它应该只显示空的而不是空的。
It sounds like you want to check if $str->ais a valid string or not. As suggested in comments by @GrumpyCrouton you can use empty().
听起来您想检查是否$str->a是有效字符串。正如@GrumpyCrouton 在评论中所建议的，您可以使用empty()。
@if( empty($str->a))
... // do somethin
@endif
