使用带有数字索引的php提取功能 [英] Using php extract function with numeric indexes

问题描述

我想使用提取函数将数组值转换为变量.作为提取功能，将数组键用作变量名，将值用作变量值.我有一个带有数字键的数组，如下所示:

I want to convert array values into variables using extract function. As extract function uses array keys as variable names and values as variable values. I have an array with numeric keys as shown:

$my_array = array(0 =>"Cat", 1=>"Dog", 2=>"Horse");
extract($my_array);

我将如何在此处使用数字键作为变量名称来访问值?还是 extract()只处理字符串键?

How i would use numeric keys here as variable names to access values? Or extract() just deal with string keys?

推荐答案

根据手册，

您必须使用关联数组；除非您使用 EXTR_PREFIX_ALL 或 EXTR_PREFIX_INVALID ，否则数字索引数组将不会产生结果.

You must use an associative array; a numerically indexed array will not produce results unless you use EXTR_PREFIX_ALL or EXTR_PREFIX_INVALID.

您可以在 extract()函数中添加前缀.在下面的示例中，这会将 var _ 前缀添加到每个实例.您可以提供任何有效的变量前缀作为第三个参数-创建的变量将在 extract()函数中反映该参数.

You can add a prefix to your extract() function. This would, in the example below, add the var_ prefix to each instance. You can supply whatever valid variable-prefix as the third argument - the created variables would reflect that parameter in the extract() function.

$my_array = array(0 =>"Cat", 1=>"Dog", 2=>"Horse");
extract($my_array, EXTR_PREFIX_ALL, "var");

现在可以通过 $ var_2 在 $ var_0 中找到结果.

The results can now be found in $var_0 through $var_2.

• 文档
• 实时演示

这篇关于使用带有数字索引的php提取功能的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！