How to retain the filled-in information after PHP fails to submit the form_PHP Tutorial

This article will introduce to you some summary methods on how to retain the filled-in information after PHP fails to submit the form. The most commonly used method is to use caching. This method may cause problems if the network speed is slow. The best way is to use ajax. .

1． Use the header header to set the cache control header Cache-control.

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header('Cache-control: private, must-revalidate'); //Support page bounce

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header('Cache-control: private, must-revalidate'); //支持页面回跳

2． Use the session_cache_limiter method.

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1.session_cache_limiter('private, must-revalidate'); //Write before the session_start method

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1.session_cache_limiter('private, must-revalidate'); //要写在session_start方法之前

The following is an introduction to the session_cache_limiter parameters:

The meaning of several parameters in session_cache_limiter is:
nocache: Of course it is not cached (for example: the form information is cleared), but public variables can be cached
private: private mode cache (for example: form information is retained, but valid within the lifetime)
private_no_cache: private mode but does not expire (form information is retained)
publice: public mode, (form information is also retained Reserved)

Set cache expiration time: session_cache_expire function setting, the default is 180 minutes.

Commonly encountered problems:

1. session_cache_limiter("private"); The form information is retained, but if I modify the submitted information, the information presented on the form page is still the information in the cache, which cannot be automatically refreshed in time. If session_cache_limiter("private"); is not used, it cannot Retain form information

Solution:

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代码如下	复制代码
session_cache_limiter( "private, must-revalidate" );即可

session_cache_limiter( "private, must-revalidate" ); That's it

Another way we can use ajax to instance

index.html template file large content:

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