JavaScript array push is not functioning as expected

Question

JavaScript array push is not functioning as expected

Having trouble getting my push function to work properly..

Here is my code snippet:

   var result = {};


dpd.timesheetsdone.get(function (timesheets, err) {
  if(err) return console.log(err);

  timesheets.forEach(function(entry, index) {

   result[entry.timesheets[0].week] = [];
   result[entry.timesheets[0].week].push(entry);
     //here is where I'm trying to push
  }
   );
    setResult(result);

});

When the code runs, it doesn't actually push the entry, it just assigns it and sets result to one item. It's not pushing as intended.

What could be causing this issue?

An example of the timesheets can be found here.

javascript arrays

Answer 1

Answer №1

The issue lies in this section:

result[entry.timesheets[0].week] = [];

Any previous data stored there will be overwritten; hence, only the latest information for that week is visible.

To prevent overwriting existing data, you should check if the assignment has been done already:

if (!result[entry.timesheets[0].week]) {
    result[entry.timesheets[0].week] = [];
}

For example:

var result = {};

dpd.timesheetsdone.get(function(timesheets, err) {
    if (err) return console.log(err);

    timesheets.forEach(function(entry, index) {

        if (!result[entry.timesheets[0].week]) {
            result[entry.timesheets[0].week] = [];
        }
        result[entry.timesheets[0].week].push(entry);
    });
    setResult(result);

});

Alternatively, to minimize object lookups:

var result = {};

dpd.timesheetsdone.get(function(timesheets, err) {
    if (err) return console.log(err);

    timesheets.forEach(function(entry, index) {
        var week = entry.timesheets[0].week;
        var weekArray = result[week];
        if (!weekArray) {
            weekArray = result[week] = [];
        }
        weekArray.push(entry);
    });
    setResult(result);

});

Answer 2

The issue lies in this section:

result[entry.timesheets[0].week] = [];

Any previous data stored there will be overwritten; hence, only the latest information for that week is visible.

To prevent overwriting existing data, you should check if the assignment has been done already:

if (!result[entry.timesheets[0].week]) {
    result[entry.timesheets[0].week] = [];
}

For example:

var result = {};

dpd.timesheetsdone.get(function(timesheets, err) {
    if (err) return console.log(err);

    timesheets.forEach(function(entry, index) {

        if (!result[entry.timesheets[0].week]) {
            result[entry.timesheets[0].week] = [];
        }
        result[entry.timesheets[0].week].push(entry);
    });
    setResult(result);

});

Alternatively, to minimize object lookups:

var result = {};

dpd.timesheetsdone.get(function(timesheets, err) {
    if (err) return console.log(err);

    timesheets.forEach(function(entry, index) {
        var week = entry.timesheets[0].week;
        var weekArray = result[week];
        if (!weekArray) {
            weekArray = result[week] = [];
        }
        weekArray.push(entry);
    });
    setResult(result);

});

JavaScript array push is not functioning as expected

Answer №1

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