Posting Data to a Connected Database

最新推荐文章于 2022-08-24 10:42:20 发布

原创最新推荐文章于 2022-08-24 10:42:20 发布 · 876 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#database #dataset #exception #datatables #table #access

在调用此方法之前，确保网格控件已保存对当前焦点行的所有更改（用户可能输入了新数据但忘记更新行）。为此，需要调用BaseView.PostEditor和ColumnView.UpdateCurrentRow方法。dataSet11对象代表一个DataSet实例，可以访问我们的表格。

The .Net data model implies that a control bound to a database using DbDataAdapter and DataTable objects does not immediately post changes after they have been made. Instead, changes are accumulated in the DataTable and you have to manually call a specific method to update the database. The XtraGrid behaves in a similar way: changes you made while editing data (adding, deleting or modifying records) are saved in a corresponding DataTable. To post these changes to the database, you should call the data adapter's System.Data.Common.DbDataAdapter.Update method.

Before calling this method, make sure that the grid control has saved all the changes made to the currently focused row (the end-user could enter new data but forget to update the row). For this purpose, you need to call the BaseView.PostEditor and ColumnView.UpdateCurrentRow methods.

The following code lists the UpdateDatasource method which posts the changes stored in the custom Suppliers and Products DataTables to a database. It is assumed that the data adapters ( oleDbDataAdapter1 and oleDbDataAdapter2) contain appropriate Update SQL statements to modify the corresponding tables in the database. By default, these statements are created by the adapter's Wizards.

The dataSet11 object represents a DataSet instance and this provides access to our tables.

C#	Copy Code
using DevExpress.XtraGrid; using DevExpress.XtraGrid.Views.Base; using System.Data.Common; //... public void UpdateDatasource(GridControl grid) { //Save the latest changes to the bound DataTable ColumnView View = (ColumnView)grid.FocusedView; if (!(view.PostEditor() && View.UpdateCurrentRow())) return; //Update the database's Suppliers table to which oleDBDataAdapter1 is connected DoUpdate(oleDbDataAdapter1, dataSet11.Tables["Suppliers"]); //Update the database's Products table to which the oleDbDataAdapter2 is connected DoUpdate(oleDbDataAdapter2, dataSet11.Tables["Products"]); } public void DoUpdate(DbDataAdapter dataAdapter, System.Data.DataTable dataTable) { try { dataAdapter.Update(dataTable); } catch(Exception ex) { MessageBox.Show(ex.Message); } }

Copy Code

using DevExpress.XtraGrid;
using DevExpress.XtraGrid.Views.Base;
using System.Data.Common;
//...
public void UpdateDatasource(GridControl grid) {
    //Save the latest changes to the bound DataTable
    ColumnView View = (ColumnView)grid.FocusedView;
    if (!(view.PostEditor() && View.UpdateCurrentRow())) return;
    
    //Update the database's Suppliers table to which oleDBDataAdapter1 is connected
    DoUpdate(oleDbDataAdapter1, dataSet11.Tables["Suppliers"]);
    //Update the database's Products table to which the oleDbDataAdapter2 is connected
    DoUpdate(oleDbDataAdapter2, dataSet11.Tables["Products"]);
}

public void DoUpdate(DbDataAdapter dataAdapter, System.Data.DataTable dataTable) {
    try {
        dataAdapter.Update(dataTable);
    } catch(Exception ex) {
        MessageBox.Show(ex.Message);
    }
}

Visual Basic	Copy Code
Imports DevExpress.XtraGrid Imports DevExpress.XtraGrid.Views.Base Imports System.Data.Common '... Public Sub UpdateDatasource(ByVal grid As GridControl) 'Save the latest changes to the bound DataTable Dim View As ColumnView = grid.FocusedView If Not (view.PostEditor() And View.UpdateCurrentRow()) Then Return 'Update the database's Suppliers table to which oleDBDataAdapter1 is connected DoUpdateTable(oleDbDataAdapter1, dataSet11.Tables("Suppliers")) 'Update the database's Products table to which the oleDbDataAdapter2 is connected DoUpdateTable(oleDbDataAdapter2, dataSet11.Tables("Products")) End Sub Public Sub DoUpdateTable(ByVal dataAdapter As DbDataAdapter, ByVal dataTable As System.Data.DataTable) Try dataAdapter.Update(dataTable) Catch ex As Exception MessageBox.Show(ex.Message) End Try End Sub

Visual Basic

Copy Code

Imports DevExpress.XtraGrid
Imports DevExpress.XtraGrid.Views.Base
Imports System.Data.Common
'...
Public Sub UpdateDatasource(ByVal grid As GridControl)
    'Save the latest changes to the bound DataTable
    Dim View As ColumnView = grid.FocusedView
    If Not (view.PostEditor() And View.UpdateCurrentRow()) Then Return

    'Update the database's Suppliers table to which oleDBDataAdapter1 is connected
    DoUpdateTable(oleDbDataAdapter1, dataSet11.Tables("Suppliers"))
    'Update the database's Products table to which the oleDbDataAdapter2 is connected
    DoUpdateTable(oleDbDataAdapter2, dataSet11.Tables("Products"))
End Sub

Public Sub DoUpdateTable(ByVal dataAdapter As DbDataAdapter, ByVal dataTable As System.Data.DataTable)
    Try
        dataAdapter.Update(dataTable)
    Catch ex As Exception
        MessageBox.Show(ex.Message)
    End Try
End Sub