PHP array_rand() function of random article function_PHP tutorial

During development, I encountered a function to refresh the page to randomly obtain articles. I used the array_rand() function in the PHP function, array_rand(array, number), which has two parameters. The array parameter represents an array you want to obtain. Number can be Select parameters. The second parameter is used to determine how many elements to select. The default is 1. . If more than one element is selected, an array containing a random key is returned, otherwise the key of the element is returned. (Remember: understand the meaning of the bold part). What is returned is an array key name, not the corresponding value in the array. When I first started using it, I thought it was returning a numerical value directly, but I couldn't get the value. My specific usage is as follows:
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