Write to Nested Dictionary (Swift 4)
I have declared a dictionary in Swift as so: var dict = [String: [String: [String]]]().
What I am trying to do now is to write to the nested dictionary. I have used both codes below, however, none of them work as the initial key does not exist:
dict["Test"]?["One"] = ["Failed"]
dict["Test"]!["One"] = ["Failed"]
What I am trying to do is to create a key for ["One"], much like how you can create a key for a normal dictionary using dict[key].
swift dictionary collections
edited Nov 11 at 22:58
Hamish
45k7103158
asked Nov 11 at 22:55
M.I
13512
add a comment |
I have declared a dictionary in Swift as so: var dict = [String: [String: [String]]]().
What I am trying to do now is to write to the nested dictionary. I have used both codes below, however, none of them work as the initial key does not exist:
dict["Test"]?["One"] = ["Failed"]
dict["Test"]!["One"] = ["Failed"]
What I am trying to do is to create a key for ["One"], much like how you can create a key for a normal dictionary using dict[key].
swift dictionary collections
edited Nov 11 at 22:58
Hamish
45k7103158
asked Nov 11 at 22:55
M.I
13512
did you solve it?
– Gustavo Vollbrecht
Nov 13 at 16:09
yes i did! thank you, but I don't know why I can't accept your answer. I don't see the green checkmark.
– M.I
Nov 13 at 20:45
add a comment |
I have declared a dictionary in Swift as so: var dict = [String: [String: [String]]]().
What I am trying to do now is to write to the nested dictionary. I have used both codes below, however, none of them work as the initial key does not exist:
dict["Test"]?["One"] = ["Failed"]
dict["Test"]!["One"] = ["Failed"]
What I am trying to do is to create a key for ["One"], much like how you can create a key for a normal dictionary using dict[key].
swift dictionary collections
edited Nov 11 at 22:58
Hamish
45k7103158
asked Nov 11 at 22:55
M.I
13512
I have declared a dictionary in Swift as so: var dict = [String: [String: [String]]]().
What I am trying to do now is to write to the nested dictionary. I have used both codes below, however, none of them work as the initial key does not exist:
dict["Test"]?["One"] = ["Failed"]
dict["Test"]!["One"] = ["Failed"]
What I am trying to do is to create a key for ["One"], much like how you can create a key for a normal dictionary using dict[key].
swift dictionary collections
swift dictionary collections
edited Nov 11 at 22:58
Hamish
45k7103158
asked Nov 11 at 22:55
M.I
13512
edited Nov 11 at 22:58
Hamish
45k7103158
asked Nov 11 at 22:55
M.I
13512
edited Nov 11 at 22:58
Hamish
45k7103158
edited Nov 11 at 22:58
Hamish
45k7103158
edited Nov 11 at 22:58
Hamish
45k7103158
45k7103158
asked Nov 11 at 22:55
M.I
13512
asked Nov 11 at 22:55
M.I
13512
asked Nov 11 at 22:55
M.I
13512
13512
did you solve it?
– Gustavo Vollbrecht
Nov 13 at 16:09
yes i did! thank you, but I don't know why I can't accept your answer. I don't see the green checkmark.
– M.I
Nov 13 at 20:45
add a comment |
did you solve it?
– Gustavo Vollbrecht
Nov 13 at 16:09
yes i did! thank you, but I don't know why I can't accept your answer. I don't see the green checkmark.
– M.I
Nov 13 at 20:45
did you solve it?
– Gustavo Vollbrecht
Nov 13 at 16:09
did you solve it?
– Gustavo Vollbrecht
Nov 13 at 16:09
yes i did! thank you, but I don't know why I can't accept your answer. I don't see the green checkmark.
– M.I
Nov 13 at 20:45
yes i did! thank you, but I don't know why I can't accept your answer. I don't see the green checkmark.
– M.I
Nov 13 at 20:45
add a comment |
2 Answers
2
active
oldest
votes
You need to instantiate every inner dictionary.
var dict = [String : [String : [String]]]()
dict["Test"] = [String : [String]]()
dict["Test"]?["One"] = ["Worked"]
print(dict)
Make sure to avoid force unwrapping.
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
add a comment |
dict is empty. There is no value for the "Test" key.
One option is to provide a default:
dict["Test", default: [:]]["One"] = ["A", "B"]
You can take this one step further:
dict["Test2", default: [:]]["Two", default: ].append("Hello")
That last line will work for any combination of the keys "Test2" and "Two" existing or not before that is used.
answered Nov 11 at 23:26
rmaddy
238k27309375
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
You need to instantiate every inner dictionary.
var dict = [String : [String : [String]]]()
dict["Test"] = [String : [String]]()
dict["Test"]?["One"] = ["Worked"]
print(dict)
Make sure to avoid force unwrapping.
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
add a comment |
You need to instantiate every inner dictionary.
var dict = [String : [String : [String]]]()
dict["Test"] = [String : [String]]()
dict["Test"]?["One"] = ["Worked"]
print(dict)
Make sure to avoid force unwrapping.
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
add a comment |
You need to instantiate every inner dictionary.
var dict = [String : [String : [String]]]()
dict["Test"] = [String : [String]]()
dict["Test"]?["One"] = ["Worked"]
print(dict)
Make sure to avoid force unwrapping.
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
You need to instantiate every inner dictionary.
var dict = [String : [String : [String]]]()
dict["Test"] = [String : [String]]()
dict["Test"]?["One"] = ["Worked"]
print(dict)
Make sure to avoid force unwrapping.
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
answered Nov 11 at 23:09
Gustavo Vollbrecht
6531515
6531515
add a comment |
add a comment |
dict is empty. There is no value for the "Test" key.
One option is to provide a default:
dict["Test", default: [:]]["One"] = ["A", "B"]
You can take this one step further:
dict["Test2", default: [:]]["Two", default: ].append("Hello")
That last line will work for any combination of the keys "Test2" and "Two" existing or not before that is used.
answered Nov 11 at 23:26
rmaddy
238k27309375
add a comment |
dict is empty. There is no value for the "Test" key.
One option is to provide a default:
dict["Test", default: [:]]["One"] = ["A", "B"]
You can take this one step further:
dict["Test2", default: [:]]["Two", default: ].append("Hello")
That last line will work for any combination of the keys "Test2" and "Two" existing or not before that is used.
answered Nov 11 at 23:26
rmaddy
238k27309375
add a comment |
dict is empty. There is no value for the "Test" key.
One option is to provide a default:
dict["Test", default: [:]]["One"] = ["A", "B"]
You can take this one step further:
dict["Test2", default: [:]]["Two", default: ].append("Hello")
That last line will work for any combination of the keys "Test2" and "Two" existing or not before that is used.
answered Nov 11 at 23:26
rmaddy
238k27309375
dict is empty. There is no value for the "Test" key.
One option is to provide a default:
dict["Test", default: [:]]["One"] = ["A", "B"]
You can take this one step further:
dict["Test2", default: [:]]["Two", default: ].append("Hello")
That last line will work for any combination of the keys "Test2" and "Two" existing or not before that is used.
answered Nov 11 at 23:26
rmaddy
238k27309375
answered Nov 11 at 23:26
rmaddy
238k27309375
answered Nov 11 at 23:26
rmaddy
238k27309375
answered Nov 11 at 23:26
rmaddy
238k27309375
238k27309375
add a comment |
add a comment |
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did you solve it?
– Gustavo Vollbrecht
Nov 13 at 16:09
yes i did! thank you, but I don't know why I can't accept your answer. I don't see the green checkmark.
– M.I
Nov 13 at 20:45