How to check if the character is alphanumeric in GO

Understanding Characters in Go as Bytes

In Go, a string is equivalent to a slice of bytes.

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Solution: Checking if a Character is Alphanumeric

To determine whether a character is alphanumeric (i.e., a letter or a digit), you can create a function that checks the byte value of the character.

Here’s an example implementation:

package main

func isAlphaNumeric(c byte) bool {
    // Check if the byte value falls within the range of alphanumeric characters
    return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9')
}

func main() {

    isAlphaNumeric('a') // true

    isAlphaNumeric('2') // true (digits are also considered alphanumeric)

    isAlphaNumeric('#') // false
}

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In the isAlphaNumeric function:
We check if the byte value c corresponds to a lowercase letter ('a' to 'z'), an uppercase letter ('A' to 'Z'), or a digit ('0' to '9').
If the condition is met, we return true; otherwise, we return false.

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Let me know if you have an alternative solution or learned something from this post.