The result of non-null str = 0 is true.

The result of a non-empty str = 0 is true & lt ;? Php & nbsp; $ str = 'asdfasdfa '; & nbsp; & nbsp; $ bool & nbsp ;=& nbsp; ($ str == 0); & nbsp non-empty str == 0 returns true

 $ Str = 'asdfasdfa ';
$ Bool = ($ str = 0 );
Echo $ bool;
?>

Here bool is true .....
This is why bool is actually true... 'data-pics = ''>
------ Solution --------------------
Upstairs

I analyzed it like this.

Echo $ str> 0 results empty
Echo $ str <0 results empty
Echo $ str = 0 Result 1

Because $ str is a string and itself is not a number, $ str is indeed false as a number, and false = 0 in php is true.

Refer to my post. when I search for a database, the varchar field uses col = 0 for the search result. if col is null, the search result is correct.
The same is true.
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