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How to send custom headers to server using DataManager in .NET WebForms ?
2 mins read
You can pass any values in the Headers of ejDataManager and retrieve them at the server-side using the Request object of the HttpRequestMessage. This can be added to the headers either in the initial load of ejGrid or while performing any server-side operations like editing/adding and retrieve them at the server-side as follows.
<div id="Grid"></div>
$("#Grid").ejGrid({
dataSource: ej.DataManager({ url: "/Home/DataSource", adaptor: new ej.UrlAdaptor() }),
allowScrolling: true,
allowFiltering: true,
allowPaging: true,
load: "load",
columns: [
{ field: "OrderID" },
{ field: "ShipCountry" },
{ field: "CustomerID" },
{ field: "EmployeeID" },
{ field: "ShipCity" }
]
});
At the load event of Grid, we have to add some values to the headers of DataManager instances.
MVC
@(Html.EJ().Grid<OrdersView>("Grid")
.Datasource(ds=>ds.URL("/Home/DataSource").Adaptor(AdaptorType.UrlAdaptor))
.AllowPaging()
.Columns(col =>
{
col.Field("OrderID").Add();
col.Field("ShipCountry").Add();
col.Field("CustomerID").Add();
col.Field("EmployeeID").Add();
col.Field("ShipCity").Add();
})
.ClientSideEvents(events => events.Load("load"))
)
Controller
public ActionResult DataSource(Syncfusion.JavaScript.DataManager dm)
{
IEnumerable Data = new NorthwindDataContext().OrdersViews.ToList();
var Field = Request.Headers.GetValues("field").ToList()[0];
var Valid = Request.Headers.GetValues("IsValid").ToList()[0];
DataResult result = new DataResult();
DataOperations operation = new DataOperations();
result.count = Data.AsQueryable().Count();
if (dm.Skip != null)
Data = operation.PerformSkip(Data, dm.Skip);
if(dm.Take != null)
Data = operation.PerformTake(Data, dm.Take);
result.result = Data;
return Json(result, JsonRequestBehavior.AllowGet);
}
ASPX
<ej:Grid id="Grid" runat="server" AllowPaging="true"> <DataManager URL="Default.aspx/Data" Adaptor="WebMethodAdaptor" /> <Columns> <ej:Column Field="OrderID" /> <ej:Column Field="ShipCountry" /> <ej:Column Field="CustomerID" /> <ej:Column Field="EmployeeID" /> <ej:Column Field="ShipCity" /> </Columns> <ClientSideEvents Load="load" /> </ej:Grid>
CodeBehind
In static methods, we cannot get the HttpRequest instance, so we have used the HttpContext.
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static object Data(Syncfusion.JavaScript.DataManager value)
{
var Field = HttpContext.Current.Request.Headers.GetValues("field").ToList()[0];
var Valid = HttpContext.Current.Request.Headers.GetValues("IsValid").ToList()[0];
IEnumerable Data = OrderRepository.GetAllRecords();
int count = Data.AsQueryable().Count();
DataOperations operation = new DataOperations();
Data = operation.Execute(Data, value);
return new { result = Data, count = count };
}
<script>
function load(args) {
//At the initial load of Grid, header is undefined
this.model.dataSource.dataSource.headers = [];//So define them as array
this.model.dataSource.dataSource.headers.push({ "field": "OrderID"});//pushing Some JSON Object
this.model.dataSource.dataSource.headers.push({ "IsValid": true });//pushing Some JSON Object
}
</script>
Below screenshot shows the header values in the post request.
Figure 1: Header values in Post Request
Figure 2: Grid
