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How to check if a string is empty in Kotlin

How to check if a string is empty in Kotlin.

Here's a step-by-step tutorial on how to check if a string is empty in Kotlin:

Step 1: Declare a string variable​

First, you need to declare a string variable that you want to check for emptiness. You can declare a string variable like this:

val myString = "Hello, World!"

Step 2: Use the isEmpty() function​

Kotlin provides a built-in function called isEmpty() that you can use to check if a string is empty. This function returns true if the string is empty (i.e., it has a length of 0), and false otherwise.

To use the isEmpty() function, you need to call it on the string variable you want to check. Here's an example:

val isEmpty = myString.isEmpty()

Step 3: Check the result​

After calling the isEmpty() function, you can check the result to determine if the string is empty or not. If the result is true, it means that the string is empty. If the result is false, it means that the string is not empty.

You can use an if statement to perform different actions based on the result. Here's an example:

if (isEmpty) {
    println("The string is empty.")
} else {
    println("The string is not empty.")
}

Step 4: Use isNullOrEmpty() for null or empty strings​

In addition to the isEmpty() function, Kotlin also provides another function called isNullOrEmpty() that you can use to check if a string is either null or empty. This function returns true if the string is null or empty, and false otherwise.

To use the isNullOrEmpty() function, you can call it on the string variable directly. Here's an example:

val isNullOrEmpty = myString.isNullOrEmpty()

Step 5: Check the result for null or empty strings​

Similar to step 3, you can check the result of the isNullOrEmpty() function to determine if the string is null or empty. If the result is true, it means that the string is null or empty. If the result is false, it means that the string is neither null nor empty.

Here's an example of using an if statement to perform different actions based on the result:

if (isNullOrEmpty) {
    println("The string is either null or empty.")
} else {
    println("The string is neither null nor empty.")
}

That's it! You now know how to check if a string is empty or null in Kotlin using the isEmpty() and isNullOrEmpty() functions.