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How to convert a string to a float or double in Kotlin

How to convert a string to a float or double in Kotlin.

Here is a step-by-step tutorial on how to convert a string to a float or double in Kotlin.

Converting a String to a Float​

To convert a string to a float in Kotlin, you can use the toFloat() function. Here's how you can do it:

  1. Declare a string variable that contains the string you want to convert to a float.
val str = "3.14"
  1. Use the toFloat() function to convert the string to a float.
val floatValue = str.toFloat()
  1. The toFloat() function returns the float value of the string. You can now use the floatValue variable as a float in your code.

Here's a complete example:

val str = "3.14"
val floatValue = str.toFloat()

// Using the floatValue variable
println(floatValue) // Output: 3.14

Converting a String to a Double​

To convert a string to a double in Kotlin, you can use the toDouble() function. Here's how you can do it:

  1. Declare a string variable that contains the string you want to convert to a double.
val str = "3.14"
  1. Use the toDouble() function to convert the string to a double.
val doubleValue = str.toDouble()
  1. The toDouble() function returns the double value of the string. You can now use the doubleValue variable as a double in your code.

Here's a complete example:

val str = "3.14"
val doubleValue = str.toDouble()

// Using the doubleValue variable
println(doubleValue) // Output: 3.14

Handling Number Format Exceptions​

When converting a string to a float or double, it's important to handle potential Number Format Exceptions that may occur if the string cannot be parsed as a valid number.

To handle such exceptions, you can use a try-catch block. Here's an example:

val str = "abc" // Invalid number string

try {
    val floatValue = str.toFloat()
    println(floatValue)
} catch (e: NumberFormatException) {
    println("Invalid number format")
}

In this example, if the string "abc" cannot be converted to a float, a NumberFormatException will be thrown. The catch block will then handle the exception and print an error message.

That's it! You now know how to convert a string to a float or double in Kotlin.