For my app, I need to simply take a key (that has multiple values attached to it) from a dictionary and pick a random one of its values to assign to a variable. I think the way to find the number of values of a key and pick a random value would be easy but assigning that value to a variable I don’t know how to do yet. Here is what I’m thinking of doing for the random value picker:
let dict: [String: [String]] = [
“Numbers“: [“One”, “Two”, “Three”],
“Letters”: [“A”, “B”, “C”]
]
var count = 0
dictKey = "Letters"
//Finding how many values are in the key "Letters"
for value in dict[dictKey] {
count = count + 1
}
print(count)
//This should be how many values there are in the "Letters" key
var randomValueNum = arc4Random_uniform(count - 1)I have never used for-in loops before so correct me if I used it incorrectly there, and if there is an easier way to do the above code, please tell me.
Now after that code, I need to extract the string from the value at [randomValueNum] (e.g. If randomValueNum was 0, the value would be "A", if it was 1, the value would be "B", etc.). Once I have that string, I need it in a varible as a String. Thanks in advance.
The values in the dictionary are arrays, so you don't need to count their contents manually:
let count = dict [dictKey]!.countYour random number number is not quite right, because the parameter to arc4random_uniform is an upper bound, not a maximum value. The returned value is always less than the number you pass in. So:
let index = arc4random_uniform (count)(Otherwise you'll never use the last element of the array.) Then you just need to go back an index into the array:
let randomlyChosenValue = dict [dictKey]! [index]Note that looking up a dictionary returns an optional value, which is why you need to unwrap ("!") the results. If you want, you could do this once and assign the resulting (non-optional) array value to a local variable.
