Remove From My Forums

Using a High order Function to return Array of Key:Value pairs

Question
0

Sign in to vote

User438705957 posted

I have incoming JSON which is an array of objects.

Each object has these properties.
{ keyname : "@keyName",
@keyName : value,
fullName : value}
A typical example of one of the array elements is:
{ keyname: "Employee_Id",
Employee_Id : 50013135,
fullName: "Wilfred Dare"}

So the object contains the name of the key ("Employee_Id") in one of the properties, along with the value of the key ("50013135") in another property, as well as the fullName associated with the key value("Wilfred Dare").

I wish to turn the array of objects into an array of key:value pairs derived from each element in the array.
So in the above example, the corresponding element in the array would be [ 50013135 ] : "Wilfred Dare"
The value of the key is the index of the array.

The resulting array would look like:
[50013135]:"Wilfred Dare"
[66699999]:"The Joker"
[36374890]:"Cat Woman"

I have achieved this using a clunky for loop, but wish to do it using .map or some other high order function.
I have not been able to achieve this so far.

Thanks for considering

Tuesday, April 9, 2019 11:33 PM

Answers

User839733648 posted

Hi Madog,

According to your description, I suggest that you could use Object.keys() and .map() to achieve your requirement.

Here is my testing code.

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title></title>
    <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
    <script>
        $(function () {
            var obj = [{ keyname: "Employee_Id", Employee_Id: 50013135, fullName: "Wilfred Dare" },
            { keyname: "Employee_Id", Employee_Id: 66699999, fullName: "The Joker" },
            { keyname: "Employee_Id", Employee_Id: 36374890, fullName: "Cat Woman" }];
            var result = Object.keys(obj).map(function (key) {
                return '['+obj[key].Employee_Id+']' + ':"' + obj[key].fullName+'"';
            });
            console.log(result);
        })
    </script>
</head>
<body>

</body>
</html>

result:

Best Regards,

Jenifer

Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM

Wednesday, April 10, 2019 6:53 AM

All replies

User839733648 posted

Hi Madog,

According to your description, I suggest that you could use Object.keys() and .map() to achieve your requirement.

Here is my testing code.

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title></title>
    <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
    <script>
        $(function () {
            var obj = [{ keyname: "Employee_Id", Employee_Id: 50013135, fullName: "Wilfred Dare" },
            { keyname: "Employee_Id", Employee_Id: 66699999, fullName: "The Joker" },
            { keyname: "Employee_Id", Employee_Id: 36374890, fullName: "Cat Woman" }];
            var result = Object.keys(obj).map(function (key) {
                return '['+obj[key].Employee_Id+']' + ':"' + obj[key].fullName+'"';
            });
            console.log(result);
        })
    </script>
</head>
<body>

</body>
</html>

result:

Best Regards,

Jenifer

Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM

Wednesday, April 10, 2019 6:53 AM

0

Sign in to vote

User438705957 posted

Thanks so much Jenifer,<br>
That’s an amazing amount of effort just to answer a complete strangers question.

Wednesday, April 10, 2019 8:36 AM

User438705957 posted

It's amazing how the extensive research I do before posting a question, is nowhere near as effective as the scant research I do after posting a question.

I have come up with a slightly different way which creates a Map I later iterate thru to create a drop-down of options, which are in effect the key:value pair.
This covers the generic case where the incoming data can be from any EF POCO that has a foreign table collection.

var optionsMap = new Map();
Object.keys(data).forEach(function (key) {
  keyVal = data[key][data[key].keyName];  // resolves to data[key]['@TheNameOfTheKey'] e.g. data[0]["Location_Id"]    
  val = data[key].FullName;       
  optionsMap.set(keyVal, val);        
});

optionsMap.forEach(function (value, key) {
  $selectOption = $('<option/>').attr({ 'value': key }).text(value);
  $inputFor.append($selectOption);
});

Cheers
Madog

Wednesday, April 10, 2019 11:07 PM

Answered by:

Using a High order Function to return Array of Key:Value pairs

Question

Answers

All replies