How to Iterate over Entries (Key-Value Pairs) in a Dictionary in Swift - Step by Step Examples

How to Iterate over Entries (Key-Value Pairs) in a Dictionary in Swift ?

Answer

To iterate over the entries (key-value pairs) in a dictionary in Swift, you can use a `for-in` loop to loop through the dictionary. This allows you to access both the key and the value of each entry.

✐ Examples

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

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

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 dictionary.
We print each key-value pair inside the loop.

Swift Program

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

// Iterate over the entries in the dictionary
print("Entries in the dictionary:")
for (key, value) in myDictionary {
    print("Key: \(key), Value: \(value)")
}

Output

Entries in the dictionary:
Key: 1, Value: One
Key: 2, Value: Two
Key: 3, Value: Three

2 Iterating over Entries and Performing Operations on Values

We can iterate over the entries in a dictionary in Swift using a `for-in` loop and perform operations on the values. This example demonstrates how to loop through the entries of a dictionary, modify the values, and print each key-value pair.

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 dictionary.
Inside the loop, we modify the value associated with each key and print the modified key-value pair.

Swift Program

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

// Iterate over the entries in the dictionary and modify values
print("Modified entries in the dictionary:")
for (key, value) in myDictionary {
    let modifiedValue = value.uppercased()
    print("Key: \(key), Value: \(modifiedValue)")
}

Output

Modified entries 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 Entries (Key-Value Pairs) in a Dictionary in Swift language with well detailed examples.

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How to Iterate over Entries (Key-Value Pairs) in a Dictionary in Swift - Step by Step Examples