If you've seen PHP-related books, you'll learn that PHP has this feature: copy when you write. So when you use foreach, you need to make changes to the data, will copy the data, if the data is very large, then will bring a certain amount of memory
foreach ($arr as & $value) {echo ' value: '. $value. 'foreach ($arr as $value) {echo ' value: '. $value. '?>Output Result:Value:oneValue:two
The first foreach with & does not change the contents of the array:Instead of the last loop, $value
Objective:The foreach structure is introduced in PhP4, which is an easy way to iterate through an array. foreach makes it easier to get key-value pairs than a traditional for-loop. Before PhP5, foreach can only be used in arrays, and after php5, it
This article provides a detailed analysis of the foreach problem in php. For more information, see
Preface:The foreach structure is introduced in php4, which is a simple way to traverse arrays. Compared with the traditional for loop, foreach can
Comparison of foreach and while loops in php. Foreach and while are both loops in php, so what is their difference between foreach and while loops, and that performance will be better, next, I will introduce the differences between foreach and while
Foreach usage references. Foreach adds nbsp; asnbsp; $ value.4;} before $ value. However, this method can easily cause errors and is not easy to find. The example is more straightforward: PHP code? Php foreach can easily modify the array unit by
Preface:The foreach structure is introduced in php4, which is a simple way to traverse arrays. Compared with the traditional for loop, foreach can more easily obtain key-value pairs. Before php5, foreach can only be used as an array; after php5,
Foreach loop instance usageIn PHP, foreach is used to loop all elements of an array. The basic foreach syntax of the author is as follows: The code is as follows:Copy code FOREACH ($ array_variable as $ value){ [Code to execute]}OrFOREACH ($
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