How to Iterate over Keys in a Dictionary in Swift

How to Iterate over Keys in a Dictionary in Swift ?

Answer

To iterate over the keys in a dictionary in Swift, you can use a `for-in` loop to loop through the `keys` property of the dictionary. This allows you to access each key individually.

✐ Examples

1 Iterating over Keys Using a `for-in` Loop

We can iterate over the keys in a dictionary in Swift using a `for-in` loop. This example demonstrates how to loop through the keys of a dictionary and print each key.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and string values.
We use a `for-in` loop to iterate over the `keys` property of the dictionary.
We print each key inside the loop.

Swift Program

var myDictionary: [Int: String] = [
    1: "One",
    2: "Two",
    3: "Three"
]

// Iterate over the keys in the dictionary
print("Keys in the dictionary:")
for key in myDictionary.keys {
    print("Key: \(key)")
}

Output

Keys in the dictionary:
Key: 1
Key: 2
Key: 3

2 Iterating over Keys and Accessing Corresponding Values

We can iterate over the keys in a dictionary in Swift using a `for-in` loop and access the corresponding values. This example demonstrates how to loop through the keys of a dictionary and print each key along with its associated value.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and string values.
We use a `for-in` loop to iterate over the `keys` property of the dictionary.
Inside the loop, we access and print the value associated with each key.

Swift Program

var myDictionary: [Int: String] = [
    1: "One",
    2: "Two",
    3: "Three"
]

// Iterate over the keys in the dictionary and access corresponding values
print("Keys and values in the dictionary:")
for key in myDictionary.keys {
    if let value = myDictionary[key] {
        print("Key: \(key), Value: \(value)")
    }
}

Output

Keys and values in the dictionary:
Key: 1, Value: One
Key: 2, Value: Two
Key: 3, Value: Three

Summary

In this tutorial, we learned How to Iterate over Keys in a Dictionary in Swift language with well detailed examples.

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How to Iterate over Keys in a Dictionary in Swift