CalculatedField.DataSource Property

Specifies the data source, associated with the calculated field.

Namespace: DevExpress.XtraReports.UI

Assembly: DevExpress.XtraReports.v19.1.dll

NuGet Packages: DevExpress.Reporting.Core, DevExpress.WindowsDesktop.Core

Declaration

C#

public override object DataSource { get; set; }

VB.NET

Public Overrides Property DataSource As Object

Property Value

Type	Description
Object	A Object representing a calculated field’s data source.

Remarks

To allow a calculated field to get access to data fields available in a data source, specify the DataSource and CalculatedField.DataMember properties. Following that, you can refer to these data fields from within the calculated field’s CalculatedField.Expression.

When a calculated field’s DataSource is empty, the field tries to obtain it from its parent (i.e., the XtraReport object to which the calculated field belongs).

To learn more, see Calculated Fields Overview.

Example

This example demonstrates how a calculated field can be created at runtime and bound to a control’s XRControl.Text property.

C#

using System;
using System.Windows.Forms;
using DevExpress.XtraReports.UI;
using DevExpress.XtraReports.Configuration;
// ...

private void button1_Click(object sender, EventArgs e) {

    // Create a report.
    XtraReport1 report = new XtraReport1();

    // Create a calculated field 
    // and add it to the report's collection.
    CalculatedField calcField = new CalculatedField();
    report.CalculatedFields.Add(calcField);

    // Define the calculated field's properties.
    calcField.DataSource = report.DataSource;
    calcField.DataMember = report.DataMember;
    calcField.FieldType = FieldType.Double;
    calcField.DisplayName = "Calculated Field";
    calcField.Name = "myField";
    calcField.Expression = "[UnitPrice] * [UnitsInStock]";

    // Bind a label's Text property to the calculated field.
    report.FindControl("xrlabel2", true).DataBindings.Add("Text", null, "Order Details.myField");

    // Bind a label's Text property to the calculated field 
    // depending on the report's data binding mode.
    if (Settings.Default.UserDesignerOptions.DataBindingMode == DataBindingMode.Bindings)
        report.FindControl("xrlabel3", true).DataBindings.Add("Text", null, "Products.myField", "{0:c2}");
    else report.FindControl("xrlabel3", true).ExpressionBindings.Add(
        new ExpressionBinding("BeforePrint", "Text", "FormatString('{0:c2}', [myField])"));

    // Display the report.
    ReportPrintTool printTool = new ReportPrintTool(report);
    printTool.ShowPreviewDialog();
}

VB.NET

Imports System
Imports System.Windows.Forms
Imports DevExpress.XtraReports.UI
Imports DevExpress.XtraReports.Configuration
' ...

Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles button1.Click

    ' Create a report.
    Dim report As New XtraReport1()

    ' Create a calculated field, 
    ' and add it to the report's collection.
    Dim calcField As New CalculatedField()
    report.CalculatedFields.Add(calcField)

    ' Define the calculated field's properties.
    calcField.DataSource = report.DataSource
    calcField.DataMember = report.DataMember
    calcField.FieldType = FieldType.Double
    calcField.DisplayName = "A Calculated Field"
    calcField.Name = "myField"
    calcField.Expression = "[UnitPrice] * [Quantity]"

    ' Bind a label's Text property to the calculated field     
    ' depending on the report's data binding mode.    
    If Settings.Default.UserDesignerOptions.DataBindingMode = DataBindingMode.Bindings Then
        report.FindControl("xrlabel3", True).DataBindings.Add("Text", Nothing, "Products.myField", "{0:c2}")
    Else
        report.FindControl("xrlabel3", True).ExpressionBindings.Add(
            New ExpressionBinding("BeforePrint", "Text", "FormatString('{0:c2}', [myField])"))    
    End If

    ' Display the report.
    Dim pt As New ReportPrintTool(report)
    pt.ShowPreviewDialog()
End Sub

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the DataSource property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

Reporting_how-to-get-a-calculated-field-value-in-the-other-calculated-fields-getresult-event-t328515/CS/XtraReport1.cs#L19

object currentRow = GetCurrentRow();
object dataSource = calculatedField_Base.DataSource == null ? DataSource : calculatedField_Base.DataSource;
string dataMember = calculatedField_Base.DataMember;

VB.NET

Reporting_how-to-get-a-calculated-field-value-in-the-other-calculated-fields-getresult-event-t328515/VB/XtraReport1.vb#L21

Dim currentRow As Object = GetCurrentRow()
Dim dataSource As Object = If(calculatedField_Base.DataSource Is Nothing, DataSource, calculatedField_Base.DataSource)
Dim dataMember As String = calculatedField_Base.DataMember