How to check if a property value exists within a Javascript array?

Question

I have an array of typed objects that is passed into my view from a controller. The requirement is to check if a string value matches any of the AdminEmailAddress string type objects within that array.

What I have tried is creating an if condition to check if the string currentUserEmail matches any of the admin emails within that list, using indexOf.

But the script breaks on the if condition:

 if (adminUserList.AdminEmailAddress.indexOf(currentUserEmail) > -1)

I also put an alert on the currentUserEmail string and the adminUserList array which are both populated with data.

The contents of the adminUserList during runtime is as follows for reference:

var adminUserList = [{"AdminID":1,"AdminDisplayName":"brianb","AdminEmailAddress":"[email protected]"},{"AdminID":2,"AdminDisplayName":"wendy","AdminEmailAddress":"[email protected]"}];

Question:

How can you check if a string matches a property value within an array?

Code:

List type containing the AdminEmailAddress property -

List type public class AdminUsers
{
    public int AdminID { get; set; }
    public string AdminDisplayName { get; set; }
    public string AdminEmailAddress { get; set; }

}

List passed in from Controller to View:

List<AdminUsers> adminList = sqlConnection.GetAdminUsers();
ViewBag.AdminUserList = adminList;

Script that contains the if condition:

<script>

    var currentUserEmail = '@ViewBag.CurrUserEmail';
    var adminUserList = @Html.Raw(Json.Encode(ViewBag.AdminUserList));


    $(document).ready(function () {

        var historyTable = $('#table').DataTable({
            "order": [[6, "desc"]]
        });


        if (adminUserList.AdminEmailAddress.indexOf(currentUserEmail) > -1)
        {
            historyTable.columns([9]).visible(false);
        }



    });
</script>

abhinsit · Accepted Answer · 2016-05-26 09:58:03Z

1

Use following function:

function checkEmailExists(currentUserEmail){

        var match = false;
        for(var i=0;i<adminUserList.length;i++){
            if(adminUserList[i]["AdminEmailAddress"].indexOf(currentUserEmail) > -1){
                match = true;
                break;
            }

        }

        return match;
    }

answered May 26, 2016 at 9:58

abhinsit

3,2574 gold badges23 silver badges26 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Emil S. Jørgensen · Accepted Answer · 2016-05-26 09:59:10Z

1

Assuming the following situation:

var adminUserList = [{"AdminID":1,"AdminDisplayName":"brianb","AdminEmailAddress":"[email protected]"},{"AdminID":2,"AdminDisplayName":"wendy","AdminEmailAddress":"[email protected]"}];
var currentUserEmail = '[email protected]';

Then you can use filter to find elements:

var matchArray = adminUserList.filter(function(element){
  return element.AdminEmailAddress === currentUserEmail;
})
alert(matchArray.length > 0);

This way you also have access to the actual results:

if(matchArray.length > 0) {
    alert(matchArray[0].AdminDisplayName)
}

answered May 26, 2016 at 9:59

Emil S. Jørgensen

6,3891 gold badge17 silver badges30 bronze badges

Comments

cs04iz1 · Accepted Answer · 2016-05-26 10:12:26Z

1

You could use the find function to find the an element of the array:

var adminUserList = [{"AdminID":1,"AdminDisplayName":"brianb","AdminEmailAddress":"[email protected]"},{"AdminID":2,"AdminDisplayName":"wendy","AdminEmailAddress":"[email protected]"}];

var mailToCheck = '[email protected]'

var adminFound =  adminUserList.find(function(admin){ return admin.AdminEmailAddres === mailToCheck});

If the user is found the user will be returned, otherwise the adminFound will be undefined.

But why do that in the front-end ? User data available in the browser, I do not think is a good practice. I suggest that you do that in your backend and return a true/false response.

answered May 26, 2016 at 10:12

cs04iz1

1,8251 gold badge20 silver badges30 bronze badges

Collectives™ on Stack Overflow

How to check if a property value exists within a Javascript array?

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related