Go If-Else Statements: Conditional Control Flow

The if statement is a fundamental control flow structure in Go, allowing you to execute different code blocks based on conditions.

Basic If Statement

The simplest form of the if statement checks a boolean condition and executes the code block if the condition is true.

if condition {
  // code to be executed if condition is true
}

None

If-Else Statement

The else clause provides an alternative code block to be executed when the if condition is false.

if condition {
  // code to be executed if condition is true
} else {
  // code to be executed if condition is false
}

None

If-Else If Chain

For multiple conditions, use else if statements. Only the first true condition's block will be executed.

if condition1 {
  // code for condition1
} else if condition2 {
  // code for condition2
} else if condition3 {
  // code for condition3
} else {
  // default code if no conditions are true
}

None

Short Declaration in If Statements

You can declare variables within the if condition, and they're accessible within the if and else blocks.

if x := someFunction(); x > 0 {
  // use x here
} else {
  // use x here
}

None

Nested If Statements

You can nest if statements for complex logic, but use them carefully to avoid making code hard to read.

if outerCondition {
  if innerCondition {
    // code
  } else {
    // code
  }
}

None

Example: Determining a Number's Range

package main

import "fmt"

func main() {
  num := 42

  if num < 0 {
    fmt.Println("Negative")
  } else if num <= 10 {
    fmt.Println("Small positive")
  } else {
    fmt.Println("Large positive")
  }
}

Large positive

Key Points

• Conditions must evaluate to boolean values.
• Braces are required for code blocks.
• Indentation improves readability.
• Consider using switch statements for multiple comparisons on the same value.

By mastering if-else statements, you'll be able to create flexible and responsive Go programs.