How to Iterate Over a Dictionary of Dictionaries in Swift - Step by Step Examples

How to Iterate Over a Dictionary of Dictionaries in Swift ?

Answer

To iterate over a dictionary of dictionaries in Swift, you can use nested `for` loops to iterate through both the outer dictionary and the inner dictionaries. This allows you to access and process each key-value pair in the nested dictionaries.

✐ Examples

1 Iterating Over a Dictionary of Dictionaries Using Nested `for` Loops

We can iterate over a dictionary of dictionaries in Swift using nested `for` loops. This example demonstrates how to declare and initialize a dictionary of dictionaries, use nested `for` loops to iterate through the outer and inner dictionaries, and print each key-value pair.

For example,

We start by declaring and initializing a dictionary of dictionaries named outerDict with string keys and integer values.
We use nested `for` loops to iterate through the outer and inner dictionaries.
We print each key-value pair.

Swift Program

var outerDict: [String: [String: Int]] = [
    "A": ["X": 1, "Y": 2],
    "B": ["Z": 3]
]

// Iterate over the dictionary of dictionaries using nested for loops
print("Iterating over dictionary of dictionaries:")
for (outerKey, innerDict) in outerDict {
    print("Outer Key: \(outerKey)")
    for (innerKey, value) in innerDict {
        print("  Inner Key: \(innerKey), Value: \(value)")
    }
}

Output

Iterating over dictionary of dictionaries:
Outer Key: A
  Inner Key: X, Value: 1
  Inner Key: Y, Value: 2
Outer Key: B
  Inner Key: Z, Value: 3

2 Iterating Over a Dynamically Created Dictionary of Dictionaries

We can iterate over a dynamically created dictionary of dictionaries in Swift using nested `for` loops. This example demonstrates how to declare a dictionary of dictionaries, add inner dictionaries dynamically, add key-value pairs to the inner dictionaries, use nested `for` loops to iterate through the outer and inner dictionaries, and print each key-value pair.

For example,

We start by declaring a dictionary of dictionaries named outerDict.
We add inner dictionaries dynamically and add key-value pairs to the inner dictionaries.
We use nested `for` loops to iterate through the outer and inner dictionaries.
We print each key-value pair.

Swift Program

var outerDict: [String: [String: Int]] = [:]

// Add inner dictionaries dynamically
outerDict["A"] = [:]
outerDict["B"] = [:]

// Add key-value pairs to the inner dictionaries
outerDict["A"]?["X"] = 1
outerDict["A"]?["Y"] = 2
outerDict["B"]?["Z"] = 3

// Iterate over the dictionary of dictionaries using nested for loops
print("Iterating over dictionary of dictionaries:")
for (outerKey, innerDict) in outerDict {
    print("Outer Key: \(outerKey)")
    for (innerKey, value) in innerDict {
        print("  Inner Key: \(innerKey), Value: \(value)")
    }
}

Output

Iterating over dictionary of dictionaries:
Outer Key: A
  Inner Key: X, Value: 1
  Inner Key: Y, Value: 2
Outer Key: B
  Inner Key: Z, Value: 3

Summary

In this tutorial, we learned How to Iterate Over a Dictionary of Dictionaries in Swift language with well detailed examples.

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How to Iterate Over a Dictionary of Dictionaries in Swift - Step by Step Examples