Maintaining data in server in EJ2 JavaScript Gantt control

2 May 202311 minutes to read

All the modified data in Gantt control can be maintained in the database using RESTful web services.

All the CRUD operations in the gantt are done through DataManager. The DataManager has an option to bind all the CRUD related data in server-side.

In the below section, we have explained how to get the edited data details on the server-side using the UrlAdaptor.

URL Adaptor

In Gantt, we can fetch data from SQL database using ADO.NET Entity Data Model and update the changes on CRUD action to the server by using DataManager support. To communicate with the remote data we are using UrlAdaptor of DataManager property to call the server method and get back resultant data in JSON format. We can know more about UrlAdaptor from here.

Please refer the link to create the ADO.NET Entity Data Model in Visual studio,

We can define data source for Gantt as instance of DataManager using url property of DataManager. Please Check the below code snippet to assign data source to Gantt.

import { Gantt } from '@syncfusion/ej2-gantt';
import { DataManager, UrlAdaptor } from '@syncfusion/ej2-data';

let dataSource: DataManager = new DataManager({
    url: '/Home/UrlDatasource',
    adaptor: new UrlAdaptor
});

let gantt: Gantt = new Gantt({
    dataSource: dataSource,
    height: '450px',
    treeColumnIndex: 1,
    taskFields: {
        id: 'TaskId',
        name: 'TaskName',
        startDate: 'StartDate',
        progress: 'Progress',
        duration: 'Duration',
        dependency: 'Predecessor',
        child: 'SubTasks'
    }
});
gantt.appendTo('#Gantt');

GanttDataSourceEntities db = new GanttDataSourceEntities();
public ActionResult UrlDatasource(DataManagerRequest dm)
{
    List<GanttData>DataList = db.GanttDatas.ToList();
    var count = DataList.Count();
    return Json(new { result = DataList, count = count });
}

We can also do CRUD operations over Gantt data and save the changes to database. By using BatchUrl property of DataManager, we can communicate with the controller method to update the data source on CRUD operation. In gantt CRUD actions on task are dependent with other tasks. For example on editing the child record on chart side, corresponding parent item also will get affect and predecessor dependency task as well get affected. So in Gantt all the CRUD operations are considered to be batch editing where you will get all the affected records as collection. Please check the below code snippet to assign controller method to this property.

import { Gantt } from '@syncfusion/ej2-gantt';
import { DataManager, UrlAdaptor } from '@syncfusion/ej2-data';

let dataSource: DataManager = new DataManager({
    url: '/Home/UrlDatasource',
    adaptor: new UrlAdaptor,
    batchUrl: "Home/BatchSave"
});

let gantt: Gantt = new Gantt({
    dataSource: dataSource,
    height: '450px',
    treeColumnIndex: 1,
    taskFields: {
        id: 'TaskId',
        name: 'TaskName',
        startDate: 'StartDate',
        progress: 'Progress',
        duration: 'Duration',
        dependency: 'Predecessor',
        child: 'SubTasks'
    }
});
gantt.appendTo('#Gantt');

public class ICRUDModel<T> where T : class
{
    public object key { get; set; }
    public T value { get; set; }
    public List<T> added { get; set; }
    public List<T> changed { get; set; }
    public List<T> deleted { get; set; }
}
GanttDataSourceEntities db = new GanttDataSourceEntities();
public ActionResult BatchSave([FromBody]ICRUDModel<GanttData> data)
{
    List<GanttData> uAdded = new List<GanttData>();
    List<GanttData> uChanged = new List<GanttData>();
    List<GanttData> uDeleted = new List<GanttData>();
    //...
    return Json(new { addedRecords = uAdded, changedRecords = uChanged, deletedRecords = uDeleted });
}

This server method will be triggered for all the CRUD operations like adding, editing and deleting actions. We can handle those each operations separately inside this method with corresponding data received in this method argument. Also, when using the UrlAdaptor, you need to return the data as JSON from the controller action and the JSON object must contain a property as result with dataSource as its value and one more property count with the dataSource total records count as its value.

Insert action

Using the added argument of the BatchUrl method we can insert the newly added row to database and return the same to client side. please find the below code example for details.

GanttDataSourceEntities db = new GanttDataSourceEntities();
public ActionResult BatchSave([FromBody]ICRUDModel<GanttData> data)
{
    List<GanttData> uAdded = new List<GanttData>();
    //Performing insert operation
    if (data.added != null && data.added.Count() > 0)
    {
        foreach (var rec in data.added)
        {
            uAdded.Add(this.Create(rec));
        }
    }
    return Json(new { addedRecords = uAdded });
    //...
}
public GanttData Create(GanttData value)
{
    db.GanttDatas.Add(value);
    db.SaveChanges();
    return value;
}

Editing action

Using the changed argument of the BatchUrl method we can update the modified records to database and return the same to client side. please find the below code example for details.

GanttDataSourceEntities db = new GanttDataSourceEntities();
public ActionResult BatchSave([FromBody]ICRUDModel<GanttData> data)
{
    List<GanttData> uChanged = new List<GanttData>();
    //Performing update operation
    if (data.changed != null && data.changed.Count() > 0)
    {
        foreach (var rec in data.changed)
        {
            uChanged.Add(this.Edit(rec));
        }
    }
    return Json(new { changedRecords = uChanged });
    //...
}
public GanttData Edit(GanttData value)
{
    GanttData result = db.GanttDatas.Where(currentData => currentData.TaskId == value.TaskId).FirstOrDefault();
    if (result != null)
    {
        result.TaskId = value.TaskId;
        result.TaskName = value.TaskName;
        result.StartDate = value.StartDate;
        result.EndDate = value.EndDate;
        result.Duration = value.Duration;
        result.Progress = value.Progress;
        result.Predecessor = value.Predecessor;
        db.SaveChanges();
        return result;
    }
    else
    {
        return null;
    }
}

Delete action

Using the deleted argument of the BatchUrl method we can remove the deleted records from database and return the same to client side. on deleting the record we need to remove its corresponding child records as well if it exist from the data base. please find the below code example for details.

GanttDataSourceEntities db = new GanttDataSourceEntities();
public ActionResult BatchSave([FromBody]ICRUDModel<GanttData> data)
{
    List<GanttData> uDeleted = new List<GanttData>();
    //Performing delete operation
    if (data.deleted != null && data.deleted.Count() > 0)
    {
        foreach (var rec in data.deleted)
        {
            uDeleted.Add(this.Delete(rec.TaskId));
        }
    }
    return Json(new { deletedRecords = uDeleted });
}
public GanttData Delete(string value)
{
    var result = db.GanttDatas.Where(currentData => currentData.TaskId == value).FirstOrDefault();
    db.GanttDatas.Remove(result);
    RemoveChildRecords(value);
    db.SaveChanges();
    return result;
}
public void RemoveChildRecords(string key)
{
    var childList = db.GanttDatas.Where(x => x.ParentId == key).ToList();
    foreach (var item in childList)
    {
        db.GanttDatas.Remove(item);
        RemoveChildRecords(item.TaskId);
    }
}