Skip to main content

How to convert a string to a boolean value in Kotlin

How to convert a string to a boolean value in Kotlin.

Here's a step-by-step tutorial on how to convert a string to a boolean value in Kotlin:

Step 1: Create a String variable​

First, you need to create a String variable that holds the value you want to convert to a boolean. For example:

val stringValue = "true"

Step 2: Use the toBoolean() function​

Kotlin provides a built-in function called toBoolean() that can be used to convert a string to a boolean value. You can simply call this function on your string variable to perform the conversion. For example:

val booleanValue = stringValue.toBoolean()

Step 3: Handle invalid string values​

Keep in mind that the toBoolean() function expects the string value to be either "true" or "false" (case-insensitive). If the string value does not match these values, it will throw a NumberFormatException. To handle this, you can use a try-catch block to catch the exception and handle it accordingly. For example:

try {
    val booleanValue = stringValue.toBoolean()
    // Do something with the boolean value
} catch (e: NumberFormatException) {
    // Handle the invalid string value
    println("Invalid boolean string value")
}

Step 4: Handling case-insensitive string values​

By default, the toBoolean() function is case-insensitive, meaning it will accept both "true" and "false" regardless of their casing. However, if you want to enforce case sensitivity, you can use the equals() function with the ignoreCase parameter set to false. For example:

val booleanValue = stringValue.equals("true", ignoreCase = false)

In this case, booleanValue will be true only if stringValue is "true" (exact casing), and false otherwise.

Step 5: Additional considerations​

  • If you want to convert a string value that is not "true" or "false" to a boolean, you will need to define your own mapping logic. For example, you can create a map that maps specific string values to boolean values and use it to perform the conversion.
  • When working with user input or external data, it's always a good practice to validate the string value before performing the conversion to avoid unexpected errors.

That's it! You've learned how to convert a string to a boolean value in Kotlin.