Angular Data Grid: Date Filter
Date filters allow you to filter date data. The Provided Filters and Simple Filters pages explain the parts of the date filter that are the same as the other provided filters. This page builds on that and explains some details that are specific to the date filter.
Date Filter Parameters
Date Filters are configured though the filterParams
attribute of the column definition. All of the parameters from Provided Filters are available:
In addition, the following parameters are also available for Date filters:
Date Selection Component
By default the grid will use the browser-provided date picker for Chrome and Firefox (as we think it's nice), but for all other browsers it will provide a simple text field. To override this and provide a custom date picker, see Date Component.
Date Filter Comparator
Dates can be represented in your data in many ways e.g. as a JavaScript Date
object, as a string in a particular format such as '26-MAR-2020'
, or something else. How you represent dates will be particular to your application.
By default, the date filter assumes you are using JavaScript Date
objects. If this is the case, the date filter will work out of the box. However, if your date is in any other format you will have to provide your own comparator
to perform the date comparisons.
The comparator
function takes two parameters. The first parameter is a JavaScript Date
object for the selected date in the filter (with the time set to midnight). The second parameter is the current value of the cell in the row being evaluated. The function must return:
- Any number < 0 if the cell value is less than the filter date.
- 0 if the dates are the same.
- Any number > 0 if the cell value is greater than the filter date.
This pattern is intended to be similar to the JavaScript compareTo(a, b)
function.
Below is an example of using a date filter with a comparator.
<ag-grid-angular
[columnDefs]="columnDefs"
/* other grid options ... */>
</ag-grid-angular>
this.columnDefs = [
// column definition configured to use a date filter
{
field: 'date',
filter: 'agDateColumnFilter',
// add extra parameters for the date filter
filterParams: {
// provide comparator function
comparator: (filterLocalDateAtMidnight, cellValue) => {
const dateAsString = cellValue;
if (dateAsString == null) {
return 0;
}
// In the example application, dates are stored as dd/mm/yyyy
// We create a Date object for comparison against the filter date
const dateParts = dateAsString.split('/');
const year = Number(dateParts[2]);
const month = Number(dateParts[1]) - 1;
const day = Number(dateParts[0]);
const cellDate = new Date(year, month, day);
// Now that both parameters are Date objects, we can compare
if (cellDate < filterLocalDateAtMidnight) {
return -1;
} else if (cellDate > filterLocalDateAtMidnight) {
return 1;
}
return 0;
}
}
}
];
Once the date comparator callback is provided, then the Date Filter is able to perform all the comparison operations it needs, e.g. 'Less Than', 'Greater Than' and 'Equals'.
Date Model vs Comparison Types
It should be noted that the Date Filter Model represents the Date as a string in format 'YYYY-MM-DD'
, however when doing comparisons the date is provided as a JavaScript Date
object as that's what date pickers typically work with. The model uses string representation to make it easier to save and avoid any timezone issues.
Example: Date Filter
The example below shows the date filter in action, using some of the configuration options discussed above:
- The Date column is using a Date Filter.
- A custom
comparator
is provided to parse the data and allow date comparisons to be made. - The native date picker is forced to be used in every browser.
-
The minimum valid year is set to
2000
, and maximum valid year is2021
. Dates outside this range will be considered invalid, and will:- Deactivate the column filter. This avoids the filter getting applied as the user is typing a year - for example suppose the user is typing the year
2008
, the filter doesn't execute for values2
,20
or200
(as the text2008
is partially typed). - Be highlighted with a red border (default theme) or other theme-appropriate highlight.
- Deactivate the column filter. This avoids the filter getting applied as the user is typing a year - for example suppose the user is typing the year
- the
inRangeFloatingFilterDateFormat
property has been set to define a custom date format, this is only shown in the floating filter panel when an in-range filter has been applied.