用于从数组中获取数据的正则表达式

Question

I have the following data in my table column information

array( 'Email: Customer One <[e-mail]>. By employee: [e-mail].',
    'By employee: [e-mail]. Department Head: Nickolas Jim.',
    'Email: Customer One <[e-mail]>. Status: currently employees.',
    'Email: Customer One <[e-mail]>. By employee: [e-mail].'
)

Etc, etc

I have a need to get the 'By employee' from the array. In other words I am in a need of regex solution

ED. I just need the By employee if present..nothing else So in above example I will have

By employee: [e-mail]
By employee: [e-mail]
By employee: [e-mail]

Answer 1

I have tested following sample code in php 5.4.5:

    <?php
$foo = array( 'Email: Customer One <[e-mail]>. By employee: [e-mail].',
              'By employee: [e-mail]. Department Head: Nickolas Jim.',
              'Email: Customer One <[e-mail]>. Status: currently employees.',
              'Email: Customer One <[e-mail]>. By employee: [e-mail].'
            );

for($i = 0; $i < count($foo); ++$i){
    if(0 >= preg_match('/\bBy employee: ([-\w._]+@[-\w]+(?:\.[-\w]+)*\.\w{2,4})\b/', $foo[$i], $matches))
        continue;  

    echo $matches[0] . "
";
    echo $matches[1] . "
";
    echo "
";  
}            

?>

output:

        By employee: [e-mail]
[e-mail]

By employee: [e-mail]
[e-mail]

By employee: [e-mail]
[e-mail]