|
VB.NET • Do It Yourself Listing 1. This Form_Load code illustrates how you can take advantage of .NET data binding in your own applications without using design-time components and their generated code. Although the block of code that handles table mappings is a bit dense, the rest of the code is straightforward. You create a Connection and Command, build a DataAdapter, fill a DataSet, and bind two textboxes and a DataGrid to the DataSet's DataTable. Private Sub frmManualCode_Load(ByVal sender _
As System.Object, ByVal e As _
System.EventArgs) Handles MyBase.Load
scnNorthwind.ConnectionString = _
"Data Source=localhost;Initial _
Catalog=Northwind;User Id=sa")
With scmCustomersSelect
.Connection = scnNorthwind
.CommandType = CommandType.Text
.CommandText = "Select * from Customers"
End With
sdaCustomers.TableMappings.AddRange( _
New System.Data.Common.DataTableMapping() _
{New System.Data.Common. DataTableMapping( _
"Table", "Customers", New _
System.Data.Common. DataColumnMapping() _
{New System.Data.Common. DataColumnMapping( _
"CustomerID", "CustomerID"), New _
System.Data.Common. DataColumnMapping( _
"CompanyName", "CompanyName"), New _
System.Data.Common. DataColumnMapping( _
"ContactName", "ContactName"), New _
System.Data.Common. DataColumnMapping( _
"ContactTitle", "ContactTitle"), New _
System.Data.Common. DataColumnMapping( _
"Address", "Address"), New _
System.Data.Common. DataColumnMapping( _
"City", "City"), New System.Data.Common. _
DataColumnMapping("Region", "Region"), _
New System.Data.Common. DataColumnMapping( _
"PostalCode", "PostalCode"), New _
System.Data.Common. DataColumnMapping( _
"Country", "Country"), New _
System.Data.Common. DataColumnMapping( _
"Phone", "Phone"), New System.Data.Common. _
DataColumnMapping("Fax", "Fax") })} )
With sdaCustomers
.SelectCommand = scmCustomersSelect
.Fill(dsNorthwind)
End With
With scbCustomers
.DataAdapter() = sdaCustomers
.RefreshSchema()
End With
txtContactName.DataBindings.Add("Text", _
dsNorthwind.Tables("Customers"), _
"ContactName")
txtCompanyName.DataBindings.Add("Text", _
dsNorthwind.Tables("Customers"), _
"CompanyName")
bmbCustomers = txtContactName. _
DataBindings("Text").BindingManagerBase
dgrCustomers.DataSource = _
dsNorthwind.Tables("Customers")
End Sub
|