Arrays are type of object that used to store group of same type of elements with fixed size of length.
Swift Dictionary type
Dictionary contains key and values of collections.
- Order is not guaranteed in key and values.
- Each value is mapped with unique keys
- Used to quickly lookup the values with key
Create Empty Dictionary
Dictionary can be created empty as given below It contains key and value types with empty braces.
var dict = [String: String]()
var employes = Dictionary<Int, String>()
print(dict)
print(employes)
Output:
[:]
[:]
Declare and initialize dictionary with literal in swift?
Add key and values to dictionary in swift?
key and values can be added with below syntax. Syntax
dictionary[key]=value
key is an value of type data and value is data that stored to dictionary. Key does not allow duplicate.
Here is an example
var dict = [String: String]()
dict["1"]="One"
dict["2"]="Two"
dict["3"]="Threee"
dict["4"]="four"
dict["4"]="five"
print(dict)
How to iterate key and values of dictionary in swift?
Dictionary can be iterated using for loop.
It iterates each element that contains key and values.
var employes = Dictionary<Int, String>()
employes[1]="john";
employes[2]="Rob";
employes[3]="Eric";
employes[4]="Andrew";
employes[5]="Mark";
print(employes)
// iterate key and values of dictionary
for (key, value) in employes {
print("\(key) : \(value)")
}
Output:
[1: "john", 2: "Rob", 3: "Eric", 5: "Mark", 4: "Andrew"]
1 : john
2 : Rob
3 : Eric
5 : Mark
4 : Andrew
How to iterate and loop dictionary keys only in swift?
dictionary.keys returns keys of an sequence. You can use forEach function for each element of an key sequence.
//Iterate keys
employes.keys.forEach { key in
print(key)
}
Output:
1
2
3
5
4
How to iterate and loop dictionary values only in swift?
Dictionary values can be iterate in two values
- one approach is to use dictionary values and call forEach function
- for loop to iterate values sequence
//Iterate values
employes.values.forEach { value in
print(value)
}
for employee in employes.values{
// do something with your sb item..
print(employee)
}
Output:
john
Rob
Eric
Mark
Andrew
john
Rob
Eric
Mark
Andrew