How to check Character is alphabetic or not in Golang?| Code examples

Learn programs on how to check whether the character is alphabetic or not in the go language. These do use an if-else statement and a switch case statement.

Alphabetic characters are characters English letters in lower and upper case. Special characters are not allowed.

Characters in go language represent the rune data type that contains the ASCII code value from 0 to 127.

Please have a look at the below golang features to have an understanding of this program better.

• Rune Data type
• if else statement
• Switch case guide

#How to check Character/rune is an alphabet or not in Golang?

In the below program, the character is stored in the rune data type.

rune represents characters in the ASCII code from 0 to 127. We have used the if-else statement to check lowercase alphabets from a to z and upper case alphabets from A to Z. Finally, print the character in an alphabet or not to the console.

package main

import (
    "fmt"
)

func checkAlphaChar(charVariable rune) {
    if (charVariable >= 'a' && charVariable <= 'z') || (charVariable >= 'A' && charVariable <= 'Z') {
        fmt.Printf("%s is an alphabet\n", string(charVariable))
    } else {
        fmt.Printf("%s is not an alphabet\n", string(charVariable))
    }

}
func main() {
    checkAlphaChar('a')
    checkAlphaChar('_')
    checkAlphaChar('Z')
    checkAlphaChar('*')

}

Output:

a is an alphabet  
\_ is not an alphabet  
Z is an alphabet

- is not an alphabet

#How to Check alphabet is ASCII using a switch case statement in Golang?

In Golang, each character represents an ASCII code from 0 to 127. ASCII values for Lowercase alphabet values are 97 to 122 and upper case alphabets are from 65 to 90.

We have used a switch case statement to check ASCII for alphabet check.

package main

import (
    "fmt"
)

func asciiAlphaCheck(r rune) {
    switch {
        case 97 <= r && r <= 122:
            fmt.Printf("%s is an alphabet\n", string(r))

        case 65 <= r && r <= 90:
            fmt.Printf("%s is an alphabet\n", string(r))
        default:
            fmt.Printf("%s is not an alphabet\n", string(r))
    }
}
func main() {
    asciiAlphaCheck('c')
    asciiAlphaCheck('|')
    asciiAlphaCheck('d')
    asciiAlphaCheck('$')

}

Output:

c is an alphabet  
| is not an alphabet  
d is an alphabet  
$ is not an alphabet