$ _ GET [] usage

$ _ GET [] has the following PHP code: & lt; ahref = & quot; example. php? Zhonglei = shipin & quot; & gt; food & lt;/a & gt; link to example. php. if $ _ GET [zhonglei] is not used in $ _ GET [],
There is such a PHP code: linking food to example. php,
If $ _ GET [zhonglei] is not used on the example. php page, but is used in another php file (this file is associated with example. php), is it okay? If not, what method can be referenced ??
I 've been struggling for a whole day! Please enlighten me !!

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Ajax works, and parameters can be passed through asynchronous GET.
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If another file (such as search. php) is included or require in example. php, you can use $ _ GET ['zhonglei'] to obtain the value in search. php.
Of course, you can also create a function in search. php, then call this function in example. php and pass the parameter.
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Well, divide all the functions into different files, include them, and write a few lines of code for test.
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After uploading the value to the example. php file, save the required value to the session or cookie.