foreach语句后的分号具有＆QUOT;有趣的＆QUOT;结果。为什么？ [英] Semicolon after foreach statement has "interesting" result. Why?

问题描述

只是有一个的 AHA 的时刻与加入; <！/ code> A 的foreach 循环结束后意外地。有趣地这并不会引发错误，但跳过（？）的循环数组中的一切，刚好碰到的最后一个元素。

Just had an AHA! moment with adding a ; after a foreach loop by accident. Funnily this didn't throw an error, but skipped(?) everything in the loops array and just touches the last element.

测试code：

$test_array = array(
    'a' => 'one',
    'b' => 'two',
    'c' => 'three'
);
foreach ( $test_array as $key => $val );
    echo $val;

问：为什么会出现这种情况。

Question: Why does this happen?

推荐答案

一个分号结束语句和foreach语句是类似的功能 - 它开辟了一个范围。如果你不打开了花括号多行范围，范围内运行到下一个分号，所以

A semicolon ends the statement and a foreach statement is similar to a function - it opens up a scope. If you do not open up a multi-line scope with curly brackets, the scope runs to the next semicolon so

foreach ( $test_array as $key => $val );

是等效

foreach ( $test_array as $key => $val ) { }

我相信这回答你的问题，为什么它的行为这样。

Which I believe answers your question as to why it behaves this way.

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