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How to copy an array in Kotlin

How to copy an array in Kotlin.

Here's a step-by-step tutorial on how to copy an array in Kotlin:

Step 1: Declare the source array​

First, you need to declare the source array that you want to copy. You can declare an array in Kotlin using the arrayOf() function. For example, let's declare an array of integers:

val sourceArray = arrayOf(1, 2, 3, 4, 5)

Step 2: Using the copyOf() function​

To copy an array in Kotlin, you can use the copyOf() function. This function creates a new array and copies the elements from the source array into the new array. The copyOf() function takes the source array and the desired length of the new array as parameters.

Here's an example of using the copyOf() function to copy the source array:

val newArray = sourceArray.copyOf(sourceArray.size)

In this example, newArray is the new array that will be created and sourceArray.size is used as the length of the new array.

Step 3: Using the clone() function​

Another way to copy an array in Kotlin is by using the clone() function. The clone() function creates a new array and copies the elements from the source array into the new array.

Here's an example of using the clone() function to copy the source array:

val newArray = sourceArray.clone()

In this example, newArray is the new array that will be created by cloning the sourceArray.

Step 4: Using the toTypedArray() function​

If you have an array of nullable elements and want to copy it without the null values, you can use the toTypedArray() function in combination with other array functions. This will create a new array without the null values.

Here's an example of using the toTypedArray() function to copy the source array without null values:

val sourceArray = arrayOfNulls<Int?>(5)
sourceArray[0] = 1
sourceArray[1] = null
sourceArray[2] = 3
sourceArray[3] = null
sourceArray[4] = 5

val newArray = sourceArray.filterNotNull().toTypedArray()

In this example, filterNotNull() filters out the null values from the sourceArray, and toTypedArray() converts the filtered list back to an array.

That's it! You have learned different ways to copy an array in Kotlin. Choose the method that suits your requirements and use it accordingly in your Kotlin projects.