从短语中删除单词，并在单词之间只留一个空格

Question

I have the following phrase and I need in PHP to remove the English Characters

$field = "日本語フレーズ A Japanese phrase A Japanese phrase 日本語フレーズ";

I have the following regular expression

trim(preg_replace('/[a-zA-Z]/', '', $field));

but this will leave with more than a single space between.

日本語フレーズ       日本語フレーズ

I need to have only one space between them. The following is the expected output.

日本語フレーズ 日本語フレーズ

Answer 1

You need to add another preg_replace function.

$str = preg_replace(/[A-Za-z]/, '', $field);
echo preg_replace(/^\h+|\h+$|(\h)+/, '\1', $str);