如何使PHP功能显示基于百分比的频率？ [重复]

Question

This question already has an answer here:

• Creating a Banner Swapping Algorithm to Rotate Ads 2 answers

here the sample case..

i want to display banner randomly by percentage based on visitor hits. for example i want to display ads 70% of visitor hits.. the problem is we don't know how many visitor is.

if it make easier we have set percentage 10%, 20%, 30% ... 100%

• and maybe also possible if we save counter per 100 hits and reset

Thanks in advanced.

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Answer 1

You don't need to know about how many visitors. The only thing you need to do is take a random number between 1 and 100, and if it is 70 or lower, it is within this 70% range.

Eventually this will work out, and display the banner to 70% of the people:

if (rand(1,100) <= 70) {
    display_banner();
}

If you want to keep this number, and show it to the user for all page views, then store it in a $_SESSION var of some sort, and based on that value display the banner.