Scope of the variable not defined within the ajax callback

Question

Scope of the variable not defined within the ajax callback

function verifyDeleteFacilitator(facilitatorId, handleData) {
var request = $.ajax({
    type: 'GET',
    url: urls.verifydeletefacilitator,
    data:{facilitatorId: facilitatorId}
}).done(function (response) {
    return handleData(response);
})
}   

var deleteButtonText = "";
verifyDeleteFacilitator(facilitator.value, function (canBeDeleted) {
    console.log(canBeDeleted);
    if (canBeDeleted == true) {
        deleteButtonText = '<button class="badge btn-danger p-2" id="confirmDeleteFacilitator" type="button"><i class="fas fa-exclamation-triangle"></i>Confirm Deletion</button>';
    }

})

console.log(deleteButtonText);

The issue with canDeleteText not being set properly lies in the scope of the callback function. Here is how you could correct it:

javascript ajax

Answer 1

Answer №1

You're not returning anything in your function .. It's important to set the var within the scope of the function unless you plan on passing it in as an argument ... For example:

canDeleteFacilitator(facilitator.value, function (canDelete) {
    var canDeleteText = "";
    console.log(canDelete);
    if (canDelete == true) {
        canDeleteText = '<button class="badge btn-danger p-2" id="deleteFacilitator" type="button"><i class="fas fa-exclamation-triangle"></i>Delete Permanently</button>';
    }
    return canDeleteText;
})

In simpler terms, keep canDeleteText within the function itself .. If you wish to use it outside the function, make sure to include a return statement at the end:

var canDeleteText = canDeleteFacilitator( callbacks );

To demonstrate this concept in action, define it as a function initially:

function canDeleteFacilitator(canDelete) {
    var canDeleteText = "";
    console.log(canDelete);
    if (canDelete == true) {
        canDeleteText = '<button class="badge btn-danger p-2" id="deleteFacilitator" type="button"><i class="fas fa-exclamation-triangle"></i>Delete Permanently</button>';
    }
    return canDeleteText;
}

var canDeleteText = canDeleteFacilitator(1); // Setting it to "true" to trigger the condition

console.log(canDeleteText);

Answer 2

You're not returning anything in your function .. It's important to set the var within the scope of the function unless you plan on passing it in as an argument ... For example:

canDeleteFacilitator(facilitator.value, function (canDelete) {
    var canDeleteText = "";
    console.log(canDelete);
    if (canDelete == true) {
        canDeleteText = '<button class="badge btn-danger p-2" id="deleteFacilitator" type="button"><i class="fas fa-exclamation-triangle"></i>Delete Permanently</button>';
    }
    return canDeleteText;
})

In simpler terms, keep canDeleteText within the function itself .. If you wish to use it outside the function, make sure to include a return statement at the end:

var canDeleteText = canDeleteFacilitator( callbacks );

To demonstrate this concept in action, define it as a function initially:

function canDeleteFacilitator(canDelete) {
    var canDeleteText = "";
    console.log(canDelete);
    if (canDelete == true) {
        canDeleteText = '<button class="badge btn-danger p-2" id="deleteFacilitator" type="button"><i class="fas fa-exclamation-triangle"></i>Delete Permanently</button>';
    }
    return canDeleteText;
}

var canDeleteText = canDeleteFacilitator(1); // Setting it to "true" to trigger the condition

console.log(canDeleteText);

Scope of the variable not defined within the ajax callback

Answer №1

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