PHP能否根据JS的判断而赋值变量，详情如下-PHP Tutorial-php.cn

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PHP能否根据JS的判断而赋值变量，详情如下

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Jun 23, 2016 pm 02:26 PM

PHP JS

var num = document.body.clientWidth;//JS获取屏幕宽度

if(num = 1){

?

}else{

?

}

pS:根据JS获取屏幕的不同宽度给php变量赋值

回复讨论(解决方案)

你可以把脚本放在php中echo出来。。

不能。
PHP在显示页面的时候就已经编译完成，不能通过JS给他赋值。

你可以用ajax在页面加载完后将值传递给php程序.

不能~
页面在后端时会把所有php语句处理完但并不执行js，等到把处理后的页面发送到前台，也就是你在浏览器里看到页面的时候，js才开始执行。

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