How does if ($variable) work? [repeat] - how exactly does if ($variable) work? [duplicate]

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Closed 8 years ago .8 Years ago close .

Possible Duplicate: May repeat ：
Regarding if statements in PHP About PHP Medium if sentence

In PHP scripts - what does an if statement like this check for? stay PHP Script - In this way if What statement will check ？

<?php if($variable){ // code to be executed } ?>  

I've seen it used in scripts several times, and now I really want to know what it "looks for". I have seen it used in scripts many times , Now I really want to know its “ effect ”.It's not missing anything; It loses nothing ;it's just a plain variable inside an if statement... I couldn't find any results about this, anywhere, so obviously I'll look stupid posting this. It's just if A common variable in the statement ... I can't find any results about this anywhere , So obviously I will look stupid when publishing this content .

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Solution ：

Reference resources ： https://stackoom.com/en/question/S5Nk