How to Effectively Remove Blank Lines from PHP Text Using Regular Expressions?

How to Eliminate Blank Lines from PHP Text

You're attempting to remove blank lines (including whitespace lines) in PHP using regular expressions, but your current approach appears ineffective. Here's a solution to address your issue:

The following regular expression will remove blank lines, whether they contain whitespace or are completely empty:

<code class="php">preg_replace("/(^[\r\n]*|[\r\n]+)[\s\t]*[\r\n]+/", "\n", $string);</code>

Let's break down the elements of this regular expression:

• Capturing Group (1): Matches blank lines or lines that start with carriage returns or line feeds.
• Alternation 1: Matches zero or more carriage returns or line feeds.
• Alternation 2: Matches one or more carriage returns or line feeds.
• Quantifier ([st]*): Matches zero or more whitespace characters (spaces or tabs).
• Quantifier ([rn] ): Matches one or more carriage returns or line feeds.

This regular expression replaces the matched blank lines with a single newline character (n). As a result, the output will remove all empty lines from your text, leaving only non-blank lines intact.

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