Convert Between Int and Char in Kotlin

By Syed Wahaj

In Kotlin, you can convert between Int and Char types using type casting or utility functions provided by the Kotlin standard library. Let’s explore two common approaches for converting between Int and Char:

1. Type Casting

You can use type casting to convert an Int to a Char by directly assigning the Int value to a Char variable:

val intValue: Int = 65
val charValue: Char = intValue.toChar()
println(charValue) // Output: 'A'

In this example, the toChar() function is used to perform the type casting from Int to Char. The resulting Char value represents the Unicode character corresponding to the given Int value. In this case, the Int value 65 corresponds to the character ‘A’.

Conversely, you can convert a Char to an Int by assigning the Char value to an Int variable:

val charValue: Char = 'A'
val intValue: Int = charValue.toInt()
println(intValue) // Output: 65

The toInt() function is used to convert the Char value to an Int. The resulting Int value represents the Unicode code point of the given Char. In this case, the character ‘A’ has a Unicode code point of 65.

2. Utility Functions

The Kotlin standard library provides utility functions for converting between Int and Char types:

val intValue: Int = 65
val charValue: Char = intValue.toChar()
println(charValue) // Output: 'A'

val charValue: Char = 'A'
val intValue: Int = charValue.toInt()
println(intValue) // Output: 65

These utility functions, toInt() and toChar(), can be directly called on Int and Char variables respectively to perform the conversion.

Additional Considerations

When converting an Int to Char, it’s important to note that the Int value should represent a valid Unicode code point. Otherwise, the resulting Char value might not correspond to a valid character.

Similarly, when converting a Char to Int, keep in mind that the resulting Int value represents the Unicode code point of the character, not necessarily its ASCII value.

Using Character Literals

In addition to type casting and utility functions, you can also use character literals to convert between Int and Char in Kotlin. Character literals represent characters directly using single quotes (”).

To convert an Int to a Char, you can assign the Int value directly to a Char variable:

val intValue: Int = 65
val charValue: Char = intValue.toChar()
println(charValue) // Output: 'A'

In this example, the Int value 65 is assigned to the Char variable charValue. Since 65 corresponds to the Unicode code point for the character ‘A’, the resulting charValue is ‘A’.

To convert a Char to an Int, you can assign the Char literal to an Int variable:

val charValue: Char = 'A'
val intValue: Int = charValue.toInt()
println(intValue) // Output: 65

In this case, the character literal ‘A’ is assigned to the Char variable charValue. The toInt() function is then used to convert charValue to an Int, which gives the Unicode code point 65.

Using character literals provides a concise and readable way to convert between Int and Char types in Kotlin.

Unicode Escape Sequences

In Kotlin, you can also use Unicode escape sequences to represent characters using their Unicode code points. Unicode escape sequences consist of the prefix \u followed by four hexadecimal digits.

For example, to represent the character ‘A’ using its Unicode code point (U+0041), you can use the escape sequence \u0041:

val charValue: Char = '\u0041'
val intValue: Int = charValue.toInt()
println(intValue) // Output: 65

In this case, the Unicode escape sequence \u0041 is assigned to the Char variable charValue. The toInt() function is then used to convert charValue to an Int, resulting in the value 65.

Unicode escape sequences are useful when you need to work with characters that are not easily representable with character literals.

Conclusion

In Kotlin, you have multiple options for converting between Int and Char types. You can use type casting, utility functions like toInt() and toChar(), character literals, or Unicode escape sequences depending on your specific requirements.

By understanding these conversion mechanisms, you can manipulate and process numeric values and characters seamlessly in your Kotlin code.