ASP.NET Core MVC Controls | ComponentOne
Working with Controls / CollectionView / Work with CollectionView / Client- Side Operations / Tracking Changes
In This Topic
    Tracking Changes
    In This Topic

    The CollectionView class can keep track of changes made to the data. It is useful in situations where you must submit changes to the server. To turn on change tracking, set the TrackChanges property to true. Once you do that, the CollectionView starts tracking the changes made to the data and exposes them using the following:

    Make sure that the DisableServerRead property of ItemSource is set to True if filtering, paging, sorting is to be performed on data available at client side only.

    The example uses C1NWind datasource, for which the configuration in the Quick Start application. The following image shows how the FlexGrid appears after the TrackChanges property is set to true.

    The following code example demonstrates how to initialize a FlexGrid, and keep a track of changes by using TrackChanges property of the CollectionView.

    In Code

    TrackChangesController.cs

    C#
    Copy Code 
    private C1NWindEntities db = new C1NWindEntities();
public ActionResult Index()
{
    return View(db);
}

    TrackChanges.cshtml

    HTML
    Copy Code 
    <h5>Change the data here</h5>
<c1-flex-grid  id="tcMainGrid" auto-generate-columns="false"
               allow-add-new="true" allow-delete="true">
    <c1-items-source source-collection="@Model" disable-server-read="true"></c1-items-source>
    <c1-flex-grid-column binding="CategoryID"></c1-flex-grid-column>
    <c1-flex-grid-column binding="CategoryName"></c1-flex-grid-column>
    <c1-flex-grid-column binding="Description" width="*"></c1-flex-grid-column>
</c1-flex-grid>
<h5>See the changes here</h5>
<h6>Items edited:</h6>
<c1-flex-grid  id="tcEditedGrid" auto-generate-columns="false"
               is-read-only="true" height="100">
    <c1-items-source source-collection="@Model"></c1-items-source>
    <c1-flex-grid-column binding="CategoryID" is-read-only="true"></c1-flex-grid-column>
    <c1-flex-grid-column binding="CategoryName"></c1-flex-grid-column>
    <c1-flex-grid-column binding="Description" width="*"></c1-flex-grid-column>
</c1-flex-grid>
<h6>Items added:</h6>
<c1-flex-grid  id="tcAddedGrid" auto-generate-columns="false"
               is-read-only="true" height="100">
    <c1-items-source source-collection="@Model"></c1-items-source>
    <c1-flex-grid-column binding="CategoryID" is-read-only="true"></c1-flex-grid-column>
    <c1-flex-grid-column binding="CategoryName"></c1-flex-grid-column>
    <c1-flex-grid-column binding="Description" width="*"></c1-flex-grid-column>
</c1-flex-grid>
<h6>Items removed:</h6>
<c1-flex-grid  id="tcRemovedGrid" auto-generate-columns="false"
               is-read-only="true" height="100">
    <c1-items-source source-collection="@Model"></c1-items-source>
    <c1-flex-grid-column binding="CategoryID" is-read-only="true"></c1-flex-grid-column>
    <c1-flex-grid-column binding="CategoryName"></c1-flex-grid-column>
    <c1-flex-grid-column binding="Description" width="*"></c1-flex-grid-column>
</c1-flex-grid>
    Script
    Copy Code 
    <script>

    $(document).ready(function () {
        //Tracking changes
        tcMainGrid = wijmo.Control.getControl('#tcMainGrid');// the flexGrid to edit the data
        tcEditedGrid = wijmo.Control.getControl('#tcEditedGrid'); // the flexGrid to record the edited items
        tcAddedGrid = wijmo.Control.getControl('#tcAddedGrid'); // the flexGrid to record the added items
        tcRemovedGrid = wijmo.Control.getControl('#tcRemovedGrid'); // the flexGrid to record the removed items
        cvTrackingChanges = tcMainGrid.itemsSource;

        tcEditedGrid.itemsSource = cvTrackingChanges.itemsEdited;
        tcAddedGrid.itemsSource = cvTrackingChanges.itemsAdded;
        tcRemovedGrid.itemsSource = cvTrackingChanges.itemsRemoved;

        // track changes of the collectionview
        cvTrackingChanges.trackChanges = true;
    });

    //Tracking changes
    var tcMainGrid = null,
        tcEditedGrid = null,
        tcAddedGrid = null,
        tcRemovedGrid = null,
        cvTrackingChanges = null;
</script>