Questions about conditional expressions in while loop

while ($i = 'AAA' && $j = 'BBB') { var_dump($i, $j); sleep(3); } 

输出结果 bool(true) string(3) "BBB"

 ------------------------------------------------------------- 在写一个后台监听程序的时候使用了while循环，于是纠结了一下`while`中的条件表达式

1. For the above code, I expected to output AAA BBB, but why is it true BBB

2. Look at this code

   while($ret = 100) { var_dump($ret) // output:100 }

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   How does the conditional expression$ret=100in the brackets here result intrueorfalse. What I want is to first assign the value100to the$retvariable, and then perform a Boolean conversion on$retto get the result.

   Hope everyone can help clear up the confusion. Thank you.

Reply content:

while ($i = 'AAA' && $j = 'BBB') { var_dump($i, $j); sleep(3); } 

输出结果 bool(true) string(3) "BBB"

 ------------------------------------------------------------- 在写一个后台监听程序的时候使用了while循环，于是纠结了一下`while`中的条件表达式

1. For the above code, I expected to output AAA BBB, but why is it true BBB

2. Look at this code

   while($ret = 100) { var_dump($ret) // output:100 }

   Copy after login

   Copy after login

   How does the conditional expression$ret=100in the brackets here result intrueorfalse. What I want is to first assign the value100to the$retvariable, and then perform a Boolean conversion on$retto get the result.

   Hope everyone can help clear up the confusion. Thank you.

if (($i = 'AAA') && ($j = 'BBB')) { var_dump($i, $j); } 

Attention&&Priority

Operator logic problem, price brackets are wrong

while (($i = 'AAA') && ( $j = 'BBB')) { var_dump($i, $j);// true bbbbb sleep(3); }

1. The comma operator causes the output bbb, V=1,2. At this time, v is 2
   2. An infinite loop. Convert to boolea can be ret = ret && true