How to Use a String as an Array Index Path to Retrieve a Value

const getValueUsingPath = (record, path) => 
    path.reduce((record, item) => record[item], record);

const record = {
    firstName: "Joe Doe",
    personalData: {
        email: "joe.doe@test.com"            
    }
};
const path = ["personalData","email"];

console.log(getValueUsingPath(record, path));

How to get the value of an Array Index Within a Dictionary to Populate the Tableview

TableViews work best when dealing with Arrays. If possible, I would turn the dictionary into an array of Dictionary<String:[String]>. So it would look something like this.

var productTags: [[String: [String]]] = [
    [product1: [tag1, tag2, tag3, tag4]],
    [product2 : [tag1, tag2, tag3, tag4, tag5]],
    [product3 : [tag1, tag2, tag3]]
]

Then from there you can return the number of product dictionaries in the array

        func tableView(_ tableView: UITableView, numberOfRowsInSection section: 
        Int) -> Int {

         return productTags.count 
    }

And from there you can access the productTagDictionaries by indexPath.row

 let productTags = productTags[indexPath.row].values.first
 cell.productName?.text = productTags?.first

Retrieve value from object having key and index as a string: 'array[0].key'

A bit nasty but quick and working way to do it is to use eval:

const field = 'Tags[0].name';
let stateValues = form.getState().values;
let tagName = eval(`stateValues.${ field }`)

Other approach might be to split and parse the field path using regexp and then traverse the object property by property.

Get the indexPath of the relevant element in a loop

Note: Make sure your array 'sateOfNewSongArray' has boolean types
of elements

Try following solutions:

Sample Code 1: According to your current code in your question.

func tapFunction(sender: UIButton) {

    // This gives me the selected indexPath
    print("ID :",sender.accessibilityIdentifier!)


    if let rowIndexString =  sender.accessibilityIdentifier, let rowIndex = Int(rowIndexString) {
        self.sateOfNewSongArray[rowIndex] = !self.sateOfNewSongArray[rowIndex]
    }
    sender.isSelected = !sender.isSelected


  for (index, element) in self.sateOfNewSongArray.enumerated() {

    if element {
       if let songName:String = songList[index] {
          selectedSongList.append(songName)
       }
    }
  }

}

Sample Code 2: More easier and concise.

func tapFunction(sender: UIButton) {

    // This gives me the selected indexPath
    print("ID :",sender.accessibilityIdentifier!)

    if let rowIndexString =  sender.accessibilityIdentifier, let rowIndex = Int(rowIndexString) {
       if let songName:String = songList[rowIndex] {
          selectedSongList.append(songName)
       }

   }

}

enumerated() is a function, returns sequence of pairs enumerating with index and element of array (by iterating elements of array)

Here is basic sample code, for your understanding. Copy and execute this code:

let songList =  [“cat”, “dog”, “elephant”]
let sateOfNewSongArray = [false, true, false]
let selectedSongList = [String]()

for (index, element) in self.sateOfNewSongArray.enumerated() {

      if element {
         if let animalName:String = songList[index] {
              selectedSongList.append(animalName)
         }
      }
}

print(“selectedSongList - \(selectedSongList)”)

How to get the index of a string in an array?

You probably need to loop over the slice and find the element that you are looking for.

func main() {
    path := "root/alpha/belta"
    key := "alpha"
    index := getIndexInPath(path, key)
    fmt.Println(index)
}

func getIndexInPath(path string, key string) int {
    parts := strings.Split(path, "/")
    if len(parts) > 0 {
        for i := len(parts) - 1; i >= 0; i-- {
            if parts[i] == key {
                return i
            }
        }
    }
    return -1
}

Note that the loop is backwards to address the logic issue that Burak Serdar pointed out that it may fail on a path like /a/a/a/a otherwise.

How to get value at a specific index of array In JavaScript?

Just use indexer

var valueAtIndex1 = myValues[1];

Update from Chrome 92 (released on: July 2021)

You can use at method from Array.prototype as follows:

var valueAtIndex1 = myValues.at(1);

See more details at MDN documentation.

How to find the array index with a value?

You can use indexOf:

var imageList = [100,200,300,400,500];
var index = imageList.indexOf(200); // 1

You will get -1 if it cannot find a value in the array.

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