Write Regular Expressions

TextGO can use regular expressions to match text with a clear structure or pattern.

What Is a Regular Expression?

A regular expression describes a text pattern with a compact, specialized syntax.

When to Use Regular Expressions

Suitable Scenarios for Regular Expressions

✅ Clearly Structured Text

• Phone numbers, ID numbers, and postal codes
• Specific format codes or numbers
• Fixed-format dates and times

✅ Deterministic Matching

• Strictly defined business formats
• Input that requires exact validation

✅ Simple and Clear Patterns

• Patterns that simple rules can describe
• Limited, predictable variations

Unsuitable Scenarios for Regular Expressions

❌ Fuzzy or Complex Patterns

• Requires contextual understanding
• Has too many variations to enumerate

❌ Patterns That Need Learning

• No clear fixed rules
• Characteristics must be learned from samples

Create a Regular Expression

Step 1: Access Regex Management

1. Open "Settings" > "Regular Expression"
2. Click the "+" button to add a new regex

Step 2: Basic Information

Type Name (Required)

• Identifies the regular expression
• Use a descriptive name

Type Icon (Optional)

• Click the current type icon to open the icon selector
• Select from "Built-in Icons" or use "Upload Custom SVG"

Step 3: Write Regular Expression

Regular Expression (Required)

• Enter a regular expression to match the type

Match Options (Optional)

• i (insensitive): Case-insensitive matching
• u (unicode): Enable Unicode-aware matching
• m (multiline): ^ and $ match at line boundaries
• s (single line): Dot matches line terminators

TextGO uses JavaScript regular expression semantics. A type matches when the pattern matches any part of the selected text. Add ^ and $ when the entire selection must match.

Use a Regular Expression

Saved regular expressions appear in the recognition type list:

1. Open "Global Shortcuts"
2. Add a new rule
3. Select the saved regular expression in "Recognize Type"
4. Configure an action and save

Regular Expression Syntax

Basic Syntax

Character Matching

Syntax	Description	Example
.	Match any single character	a.c matches abc, a1c
\d	Match a digit (0-9)	\d{3} matches 123
\D	Match a non-digit	\D+ matches abc
\w	Match a word character	\w+ matches hello_123
\W	Match a non-word character	\W+ matches @#$
\s	Match whitespace	\s+ matches space, tab
\S	Match non-whitespace	\S+ matches hello
[abc]	Match a, b, or c	[0-9] matches any digit
[^abc]	Match anything except a, b, or c	[^0-9] matches non-digit

Quantifiers

Syntax	Description	Example
*	0 or more times	ab* matches a, ab, abb
+	1 or more times	ab+ matches ab, abb
?	0 or 1 time	ab? matches a, ab
{n}	Exactly n times	a{3} matches aaa
{n,}	At least n times	a{2,} matches aa, aaa
{n,m}	n to m times	a{2,4} matches aa, aaa, aaaa

Position Matching

Syntax	Description	Example
^	Start of string	^hello matches hello at the start
$	End of string	world$ matches world at the end
\b	Word boundary	\bword\b matches the whole word
\B	Non-word boundary	\Bword matches without a leading word boundary

Grouping and Alternation

Syntax	Description	Example
(abc)	Group	(ab)+ matches ab, abab
a|b	a or b	cat|dog matches cat or dog
(?:abc)	Non-capturing group	(?:ab)+ matches without capturing

Escape Characters

Syntax	Description
\.	Literal dot
\*	Literal asterisk
\\	Literal backslash
\[	Literal left bracket
\(	Literal left paren