javascript The array is showing up as blank

Question

javascript The array is showing up as blank

I am trying to return the entire object where linkable is set to true. Even though I am pushing the objects, the this.releaseDescriptionDatesArray remains empty. It seems like my logic is correct, so not sure why the array is not populating.

for (const item of this.datesArray) {
          for (const attribute in item) {
            if (attribute === 'linkable' && item[attribute] === true) {
              this.releaseDescriptionDatesArray.push(item); // data is being pushed 

              console.log(this.releaseDescriptionDatesArray,  "datesArr"); // data is not showing here 
            }
          }
        }
    console.log(this.releaseDescriptionDatesArray,  "datesArr"); // data doesn't appear here 
      }

Sample data

       datesArray =  [ {
           "type": "disasterRecovery",
           "date": "2019-07-28",
           "releaseWindow":       {
              "start": null,
              "end": null
           },
           "description": "Disaster Recovery",
           "linkable": true
        },
           {
           "type": "nooutageRelease",
           "date": "2019-08-03",
           "releaseWindow":       {
              "start": "2019-08-04T00:00:00",
              "end": "2019-08-04T23:59:59"
           },
           "description": "Infrastructure Release (No Outage)",
           "linkable": true
        }]

javascript

Answer 1

Answer №1

If you're aware that the attribute linkable exists in every item, there's no need to parse through each attribute and check if any of them are linkable, and then verify if it's true.

Moreover, since you are strictly comparing your values (===), 'true' !== true, which may be why your array is empty. To address this, you could utilize the filter function on your array with a callback that specifically checks if linkable is true. This approach will streamline your code significantly.

let datesArray = [{
        "type": "disasterRecovery",
        "date": "2019-07-28",
        "releaseWindow": {
            "start": null,
            "end": null
        },
        "description": "Disaster Recovery",
        "linkable": true
    },
    // Changed value of this item for testing purposes
    {
        "type": "nooutageRelease",
        "date": "2019-08-03",
        "releaseWindow": {
            "start": "2019-08-04T00:00:00",
            "end": "2019-08-04T23:59:59"
        },
        "description": "Infrastructure Release (No Outage)",
        "linkable": false
    }
];

// This callback ensures that date.linkable is not null,
// and its value is true.
// If the attribute were null (or undefined), it would evaluate as "false-y" and hence
// not be included in the final array.
// The last part also verifies that the value is an actual boolean (see Lain's comment)
let output = datesArray.filter((date) => date.linkable && date.linkable === true);

console.log(output)

Answer 2

If you're aware that the attribute linkable exists in every item, there's no need to parse through each attribute and check if any of them are linkable, and then verify if it's true.

Moreover, since you are strictly comparing your values (===), 'true' !== true, which may be why your array is empty. To address this, you could utilize the filter function on your array with a callback that specifically checks if linkable is true. This approach will streamline your code significantly.

let datesArray = [{
        "type": "disasterRecovery",
        "date": "2019-07-28",
        "releaseWindow": {
            "start": null,
            "end": null
        },
        "description": "Disaster Recovery",
        "linkable": true
    },
    // Changed value of this item for testing purposes
    {
        "type": "nooutageRelease",
        "date": "2019-08-03",
        "releaseWindow": {
            "start": "2019-08-04T00:00:00",
            "end": "2019-08-04T23:59:59"
        },
        "description": "Infrastructure Release (No Outage)",
        "linkable": false
    }
];

// This callback ensures that date.linkable is not null,
// and its value is true.
// If the attribute were null (or undefined), it would evaluate as "false-y" and hence
// not be included in the final array.
// The last part also verifies that the value is an actual boolean (see Lain's comment)
let output = datesArray.filter((date) => date.linkable && date.linkable === true);

console.log(output)

Answer 3

Answer №2

item[attribute] === true

Ensure you are using boolean true, not the string 'true'

for (let item of datesArray) {
          for (let attribute of Object.keys(item)) {
            if (attribute === 'linkable' && item[attribute] === true) {
              releaseDescriptionDatesArray.push(item); // data found 
              console.log(attribute)
              console.log(this.releaseDescriptionDatesArray, "datesArr");
            }
          }
}

Answer 4

item[attribute] === true

Ensure you are using boolean true, not the string 'true'

for (let item of datesArray) {
          for (let attribute of Object.keys(item)) {
            if (attribute === 'linkable' && item[attribute] === true) {
              releaseDescriptionDatesArray.push(item); // data found 
              console.log(attribute)
              console.log(this.releaseDescriptionDatesArray, "datesArr");
            }
          }
}

javascript The array is showing up as blank

Answer №1

Answer №2

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