DOCUMENT:Q149092 11-JAN-2001 [vbwin] TITLE :HOWTO: Add Records and Edit Data in a DBGrid Cell PRODUCT :Microsoft Visual Basic for Windows PROD/VER: OPER/SYS: KEYWORDS:kbcode kbCtrl kbVBp400 ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 - Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 - Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 - Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 - Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 ------------------------------------------------------------------------------- SUMMARY ======= This article describes how to programmatically edit the data and add new records to a DBGrid control. You can change the contents of a cell and those changes will appear on the screen, but they are not written to the data source bound to the DBGrid control. To write these changes to the data source, you must instead edit the underlying recordset. MORE INFORMATION ================ The following example creates a simple database containing one table with four fields and five records. Each record is a number in the field. The database is going to be the data source. When you click on a cell, the data in that cell is shown in a TextBox. When you change the contents of that cell, the changes are shown on the DBGrid control. However, when you execute the UpdateControls method through a command button, the changes disappear from the cell, indicating the data source was not updated. You must click the Update Recordset button when you make your changes in the TextBox to ensure that the changes are written to the data source. The Update Recordset button updates the underlying recordset of the Data control. Since the DBGrid control is bound to the Data control, the changes appear in the DBGrid control. Creating the Sample Application ------------------------------- The following sample application demonstrates how to edit the contents of a DBGrid cell: 1. Start Visual Basic. Once it is running, on the File menu, click New Project. Add a Data control, a DBGrid control, a TextBox, and three Command buttons. Set the following properties for each control: Control Default Name Property Value ----------------------------------------------------- DBGrid DBGrid1 DataSource Data1 2. Copy the following code sample to the Form1 code window: Option Explicit Dim rs1 As Recordset Dim db As Database Dim td As TableDef Dim fl As Field Dim igRow As Integer, igColumn As Integer Dim iFields As Integer, iRecords As Integer Dim vargBookmark As Variant Private Sub Command1_Click() ' The Create Database button: By clicking this button, you create ' a database with four fields and five records. Set db = CreateDatabase("C:\test.mdb", dbLangGeneral) Set td = db.CreateTableDef("Table1") ' After you create the database, you need to add fields to it. For iFields = 1 To 4 ' The last number can be changed to the ' number of fields you want in the database. Set fl = td.CreateField("Field " & CStr(iFields), dbText) td.Fields.Append fl Next iFields db.TableDefs.Append td ' Now that you have added fields to the database, you need to add ' some records through a recordset. Set rs1 = db.OpenRecordset("Table1", dbOpenTable) For iRecords = 1 To 5 'For each row rs1.AddNew 'Add a new record For iFields = 1 To 4 ' For each field in the record, add rs1("Field " & CStr(iFields)) = CStr(iFields) ' a number. Next iFields rs1.Update Next iRecords ' Close both the recordset and database. rs1.Close db.Close ' Populate the DBGrid control with the contents of the Recordset. Set db = OpenDatabase("C:\test.mdb") Set rs1 = db.OpenRecordset("Select * from Table1") Set Data1.Recordset = rs1 Command1.Visible = False Command2.Visible = True Command4.Visible = True End Sub Private Sub Command2_Click() ' The Update Database button: By clicking this button, you save ' the contents of the text box to the database. Since the contents ' of the recordset are being modified, the contents are saved to ' the database after you execute the Update method. Data1.Recordset.Edit Data1.Recordset.Fields(igColumn) = Text1.Text Data1.Recordset.Update End Sub Private Sub Command3_Click() ' The Update DBGrid button: By clicking this button, you execute ' the UpdateControls method on the Data control to demonstrate ' that changing the cell in a bound DBGrid control does not save ' the new information to the database. To save these changes, you ' must modify the underlying recordset from the Data control. Data1.UpdateControls End Sub Private Sub Command4_Click() ' The Add New Record button: By clicking this button, you add new ' records to the recordset. Use the following code to add a new ' record to the DBGrid control. ' Set DBGrid and Data Control Properties to allow new records to ' be added. DBGrid1.AllowAddNew = True Data1.EOFAction = vbAddNew Data1.Recordset.MoveLast Data1.Recordset.MoveNext DBGrid1.Row = DBGrid1.VisibleRows - 1 Data1.Recordset.AddNew For iFields = 1 To 4 ' For each field in the record, ' add the contents of the text box. Data1.Recordset("Field " & CStr(iFields)) = Text1.Text Next iFields Data1.Recordset.Update End Sub Private Sub DBGrid1_Change() Command3.Visible = True End Sub Private Sub DBGrid1_MouseUp(Button As Integer, Shift As Integer, _ X As Single, Y As Single) Command2.Visible = True igColumn = DBGrid1.ColContaining(X) igRow = DBGrid1.RowContaining(Y) vargBookmark = DBGrid1.RowBookmark(igRow) Text1.Text = DBGrid1.Columns(igColumn).CellValue(vargBookmark) End Sub Private Sub Form_Load() Command1.Visible = False Command2.Visible = False Command3.Visible = False Command4.Visible = False Command1.Caption = "Create Database" Command2.Caption = "Update Database" Command3.Caption = "Update DBGrid" Command4.Caption = "Add New Record" ' If the database does not exist, show the Create Database button. If Dir("C:\test.mdb") = "" Then Command1.Visible = True Else ' Open an existing database. Set db = OpenDatabase("C:\test.mdb") Set rs1 = db.OpenRecordset("Select * from Table1") Set Data1.Recordset = rs1 Command4.Visible = True End If End Sub Private Sub Text1_Change() Command2.Visible = True End Sub Running the Sample Application ------------------------------ 1. On the Run menu, click Start, or press F5. 2. Click on a cell on the DBGrid control and change the contents of that cell. Click the Update DBGrid button. Note that your changes disappear from the DBGrid. Clicking on a blank area on the DBGrid control gives error 6148 - Invalid row number. 3. Click on a cell. Note that the contents of the cell appear on the TextBox. Change the contents of the TextBox and then click the Update Recordset button. Note that your changes now appear on the DBGrid control. 4. Click the Add New Records button to add a new record to the DBGrid control. The contents of the text box will be added as a new record. ====================================================================== Keywords : kbcode kbCtrl kbVBp400 Technology : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch Issue type : kbhowto ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. 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