正则表达式解析跟随五个特定前缀之一的行中的所有单词

Question

Consider

$email = "Name: John Smith 

          Phone: [phone]
          ...";

Suppose I have the code above, and I need to filter the line after the word "Name: ". I have been doing:

if (preg_match("/Name:*? (.*)/m", $email, $g) === 1){
    echo $g[1]."
"; //John Smith
}

What is a way to write the regex statement if the string didn't explicitly start with the word "Name: ", but one of 5 variations of it? Here are the five different formats I am working with:

• Name:
• Full Name:
• F. Name:
• First/Last Name:
• Name.

Answer 1

This can be done with several different possible patterns.

This is the php code to demonstrate your pattern implementation

$email='Name: John Smith
        Phone: [phone]
        ...';

if(preg_match('/Name[:.] \K[^
]*/',$email,$g)){
    echo $g[0]; //John Smith
}

echo "

---

";

$mult='Name: John Smith
        Phone: [phone]
        ...
        Name. Jane Smith
        Phone: [phone]
        ...
        First/Last Name: Joe Smith
        Phone: [phone]
        ...
';

var_export(preg_match_all('/Name[:.] \K[^
]*/',$mult,$g)?$g[0]:'fail');

Pattern #1: (more lenient) /Name[:.] \K[^ ]*/ Demo

Pattern #2: (more literal) ~(?:Name.|(?:F(?:. |ull |irst/Last ))?Name:) \K[^ ]*~ Demo

Some notes:

• [:.] means match either of the characters (colon or dot).
• \K means "start the fullstring match from this point in the pattern".
• [^ ]* means match zero or more characters that are not line return or new line characters.
• the delimiter in Pattern #2 is changed from / to ~ so that the slash between irst and Last doesn't have to be escaped.
• the m flag is not necessary.