Go String Data Type

 Go String Data Type – Complete Guide with Examples

In Go (Golang), the string data type is used to store textual data, such as names, messages, file paths, and JSON content.

Go strings are simple, powerful, Unicode-aware, and immutable, which makes them safe and efficient.

 What Is a String in Go?

A string is a sequence of bytes representing text, usually encoded in UTF-8.

Example

•  Text data
•  UTF-8 support
•  Immutable

Declaring String Variables

Using var

Using Short Declaration (:=)

•  Clean
•  Type inferred automatically

Zero Value of String

If a string is declared but not initialized, its zero value is an empty string ("").

Output

•  No nil
•  Safe default value

 String Immutability (Very Important)

Strings in Go are immutable, meaning you cannot change individual characters.

 Invalid

•  Strings cannot be modified directly
• Create a new string instead

 String Length

Use len() to get the number of bytes, not characters.

•  For Unicode strings, length may differ from character count.

 String Indexing

You can access bytes using index.

•  Indexing gives bytes
•  Convert to string for characters

String Concatenation

Using +

Using fmt.Sprintf

•  Better for complex formatting

 Raw String Literals (Backticks)

Go supports raw strings using backticks `.

•  Preserves formatting
•  No escape characters

 Interpreted String Literals (Double Quotes)

•  Supports escape sequences

 Common Escape Characters

String Comparison

Strings can be compared using comparison operators.

•  Lexicographical comparison

Looping Through a String

Using for with range (Recommended)

•  Unicode-safe
•  Uses rune

 Strings to Rune / Byte Conversion

Strings to Byte Slice

String to Rune Slice

•  Useful for modification
•  Required for Unicode handling

String Functions (strings Package)

•  Powerful built-in utilities

Common Mistakes

• Trying to modify string characters
•  Confusing bytes with characters
•  Using len() for Unicode length
•  Heavy string concatenation in loops

 Best Practices for Strings in Go

•  Use range for Unicode strings
•  Use strings.Builder for heavy concatenation
•  Prefer raw strings for multi-line text
•  Understand immutability
•  Use standard library functions

 Interview Questions: Go String

1. Are strings mutable in Go?
No.

2. Zero value of string?
Empty string ("").

3. Does len() return characters?
No, it returns bytes.

4. What type does range return for strings?
rune.

5. Difference between raw and interpreted strings?
Raw strings ignore escape sequences.

Summary

•  Strings store text data
•  Immutable and UTF-8 encoded
•  Zero value is empty string
• len() returns bytes
•  Rich standard library support

Mastering the Go string data type is essential for text processing, APIs, and real-world Go applications