Parameter Class

A method or constructor parameter of an ObjectDataSource.

Namespace: DevExpress.DataAccess.ObjectBinding

Assembly: DevExpress.DataAccess.v18.1.dll

Declaration

C#

public sealed class Parameter :
    DataSourceParameterBase

VB.NET

Public NotInheritable Class Parameter
    Inherits DataSourceParameterBase

Remarks

A collection of Parameter objects is returned by the following properties.

• ObjectDataSource.Parameters

  To bind an ObjectDataSource to a method, do the following.

  1. Call the ObjectDataSource.BeginUpdate method.
  2. Assign the method’s name to the ObjectDataSource.DataMember property and specify this method’s parameters (the ObjectDataSource.Parameters collection must contain parameters that are required to call this method and obtain the data).
  3. Call the ObjectDataSource.EndUpdate method.

• ObjectConstructorInfo.Parameters

  If it is required that on calling the ObjectDataSource.Fill method, an ObjectDataSource should create an instance of the type specified by its ObjectDataSource.DataSource property, use the ObjectDataSource.Constructor property to specify the required constructor parameters. To assign a constructor without parameters, use the static ObjectConstructorInfo.Default object.

  For a code sample, see the following example online: How to programmatically generate ObjectDataSource and map object data source constructor parameters to report parameters.

  Set the ObjectDataSource.Constructor property to null for the ObjectDataSource to never try to create an object instance (if you need to manually create and assign it, or when binding to a static member).

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the Parameter class.

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#

how-to-create-data-access-library-data-sources-at-runtime-t424210/CS/ObjectDataSourceSnippets/Code.cs#L21

//this line of code allows passing a parameter value to a parametrized constructor of an underlying data source object
var parameter = new DevExpress.DataAccess.ObjectBinding.Parameter("p1", typeof(int), 3);
objds.Constructor = new DevExpress.DataAccess.ObjectBinding.ObjectConstructorInfo(parameter);

objectdatasource-how-to-provide-a-custom-parameter-editor-t246429/CS/CustomRepositoryItem/XtraReport1.cs#L22

objectDataSource1.Parameters.Clear();
objectDataSource1.Parameters.Add(new Parameter("customer", typeof(Person), new Person { FirstName = "Jack", LastName = "Johnson" }));
objectDataSource1.EndUpdate();

VB.NET

how-to-create-data-access-library-data-sources-at-runtime-t424210/VB/ObjectDataSourceSnippets/Code.vb#L18

'this line of code allows passing a parameter value to a parametrized constructor of an underlying data source object
Dim parameter = New DevExpress.DataAccess.ObjectBinding.Parameter("p1", GetType(Integer), 3)
objds.Constructor = New DevExpress.DataAccess.ObjectBinding.ObjectConstructorInfo(parameter)

objectdatasource-how-to-provide-a-custom-parameter-editor-t246429/VB/CustomRepositoryItem/XtraReport1.vb#L24

objectDataSource1.Parameters.Clear()
objectDataSource1.Parameters.Add(New Parameter("customer", GetType(Person), New Person With {.FirstName = "Jack", .LastName = "Johnson"}))
objectDataSource1.EndUpdate()

Implements

IParameter

Inheritance

Object

DataSourceParameterBase

Parameter