In powershell you can use -match or -notmatch to identify string patterns using regular expression characters:
Match exact characters anywhere in the original string:
PS C:> "Ziggy stardust" -match "iggy"
A period . will match a single character:
PS C:> "cat" -match "c.t"
PS C:> "Ziggy stardust" -match "s..rdust"
Match any (at least one) of the characters - place the options in square brackets [ ]
PS C:> "Ziggy stardust" -match "Z[xyi]ggy"
Match a range (at least one) of characters in a contiguous range [n-m]
PS C:> "Ziggy stardust" -match "Zigg[x-z] Star"
Match any but these, a caret (^) will match any character except those in brackets
PS C:> "Ziggy stardust" -match "Zigg[^abc] Star"
Match the beginning characters: ^
PS C:> "Ziggy stardust" -match "^zig"
Match the end characters: $
PS C:> "Ziggy stardust" -match "dust$"
Match zero or more instances of the preceding character: *
PS C:> "Ziggy stardust" -match "g*"
Match zero or one instance of the preceding character: ?
PS C:> "Ziggy stardust" -match "g?"
Match the character that follows as an escaped character
PS C:> "Ziggy$" -match "Ziggy\$"
Match any character in a character class: \p{name}
Supported names are Unicode groups and block ranges for example, Ll (Letter, Uppercase), Nd (Number, Decimal Digit), Z (All separators), IsGreek, IsBoxDrawing.
PS C:> "ZiGGY Stardust" -match "\p{Ll}+"
Match text not included in groups and block ranges: \P{name} .
PS C:> 1234 -match "\P{Ll}+"
Match any word character: \w This is equivalent to [a-zA-Z_0-9]
PS C:> "Ziggy stardust" -match "\w+"
Match any nonword character \W This is equivalent to [^a-zA-Z_0-9]
PS C:> "Ziggy stardust" -match " \W+"
Match any white-space: \s This is equivalent to [ \f\n\r\t\v]
PS C:> "Ziggy stardust" -match "\s+"
Match any non-white-space: \S This is equivalent to [^ \f\n\r\t\v]
PS C:> "Ziggy stardust" -match "\S+"
Match any decimal digit: \d This is equivalent to \p{Nd} for Unicode and [0-9] for non-Unicode
PS C:> 12345 -match "\d+"
Match any nondigit: \D This is equivalent to \P{Nd} for Unicode and [^0-9] for non-Unicode
PS C:> "Ziggy stardust" -match "\D+"
In addition to the above Powershell also supports the quantifiers available in .NET regular expressions, these allow even more specific criteria such as: the string must match at least 5, but no more than 10 items.
The .Net framework uses a traditional NFA regex engine, to learn more about regular expressions look for the book Mastering Regular Expressions by Jeffrey Friedl
“Mere enthusiasm is the all in all. . . .Passion and expression are beauty itself.” - William Blake
Related:
Comparison -like, -lt, -gt, -eq, -ne, -match
Wildcards - Match multiple items
