Write Regular Expressions

In addition to machine learning models, TextGO also supports using regular expressions to precisely match text patterns. Regular expressions are suitable for matching text types with clear structures and rules.

What is Regular Expression

A regular expression (Regular Expression) is a powerful tool for matching string patterns. It uses special syntax to describe the structure and characteristics of text.

When to Use Regular Expressions

Suitable Scenarios for Regular Expressions

✅ Text with Clear Structure

• Including phone numbers, ID numbers, postal codes, etc.
• Specific format codes or numbers
• Fixed format dates and times

✅ Requires 100% Accuracy

• Critical business domains like finance and healthcare
• Scenarios requiring strict validation

✅ Simple and Clear Patterns

• Cases that can be described with simple rules
• Limited and controllable variation range

Unsuitable Scenarios for Regular Expressions

❌ Fuzzy or Complex Patterns

• Requires understanding contextual semantics
• Highly variable, difficult to enumerate all cases

❌ Patterns That Need Learning

• No clear fixed rules
• Needs to learn characteristics from many samples

Create 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

Regex Name (Required)

• Used to identify the regular expression
• Recommend using a descriptive name

Regex Icon (Optional)

• Click the icon selector to choose an icon
• Supports built-in icon library
• Supports uploading custom SVG icons

Step 3: Write Regular Expression

Regex Pattern (Required)

• Enter the regular expression pattern

Match Flags (Optional)

• i: Case insensitive match
• u: Match with full unicode
• m: ^ and $ match start/end of line
• s: Dot matches newline

Use Regular Expression

Created regular expressions will automatically appear in the recognition type list:

1. Open "Global Shortcuts"
2. Add a new rule
3. Select your created regular expression in "Recognition Type"
4. Configure the corresponding action and save

Regular Expression Syntax

Basic Syntax

Character Matching

Syntax	Description	Example
.	Match any single character	a.c matches abc, a1c
\d	Match digit (0-9)	\d{3} matches 123
\D	Match non-digit	\D+ matches abc
\w	Match word character	\w+ matches hello_123
\W	Match non-word character	\W+ matches @#$
\s	Match whitespace	\s+ matches space, tab
\S	Match non-whitespace	\S+ matches hello
[abc]	Match a or b or c	[0-9] matches any digit
[^abc]	Not match a, b, 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 must start with hello
$	End of string	world$ must end with world
\b	Word boundary	\bword\b matches complete word
\B	Non-word boundary	\Bword word inside another word

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 but not capture

Escape Characters

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