How to Filter a Dictionary Based on Keys in Swift - Step by Step Examples

How to Filter a Dictionary Based on Keys in Swift ?

Answer

To filter a dictionary based on keys in Swift, you can use the `filter` method and a dictionary comprehension. This allows you to create a new dictionary with the key-value pairs that satisfy a specific condition based on keys.

✐ Examples

1 Filtering a Dictionary Based on Keys Using `filter`

We can filter a dictionary based on keys in Swift using the `filter` method. This example demonstrates how to declare and initialize a dictionary, use the `filter` method to filter the dictionary based on keys, and print the filtered dictionary.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and string values.
We use the `filter` method to filter the dictionary to include only keys that are greater than 1.
We use a dictionary comprehension to create a new dictionary with the filtered items.
We print the filtered dictionary.

Swift Program

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

// Filter the dictionary to include only keys greater than 1
let filteredDict = myDictionary.filter { $0.key > 1 }

// Print the filtered dictionary
print("Filtered dictionary:")
for (key, value) in filteredDict {
    print("Key: \(key), Value: \(value)")
}

Output

Filtered dictionary:
Key: 2, Value: Two
Key: 3, Value: Three

2 Filtering a Dictionary to Include Only Specific Keys

We can filter a dictionary to include only specific keys in Swift using the `filter` method. This example demonstrates how to declare and initialize a dictionary, use the `filter` method to filter the dictionary to include only the keys 1 and 3, and print the filtered dictionary.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and string values.
We use the `filter` method to filter the dictionary to include only the keys 1 and 3.
We use a dictionary comprehension to create a new dictionary with the filtered items.
We print the filtered dictionary.

Swift Program

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

// Filter the dictionary to include only the keys 1 and 3
let filteredDict = myDictionary.filter { $0.key == 1 || $0.key == 3 }

// Print the filtered dictionary
print("Filtered dictionary:")
for (key, value) in filteredDict {
    print("Key: \(key), Value: \(value)")
}

Output

Filtered dictionary:
Key: 1, Value: One
Key: 3, Value: Three

Summary

In this tutorial, we learned How to Filter a Dictionary Based on Keys in Swift language with well detailed examples.

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How to Filter a Dictionary Based on Keys in Swift - Step by Step Examples