Adding CheckBox Control to DataGrid Control
Both for standalone applications and for web-based applications, accessing data has become a major programming task for modern software programming. Microsoft's ADO.NET technology has a solution for many of the problems associated with data access. DataGrid control holds an important status among the important parts of ADO.NET. We will find a section below on DataGrid and other related classes and how the user can play with them. The versatile DataGrid control displays tabular data and supports selecting, sorting, and editing the data. Each data field is displayed in a separate column in the order it is stored in the database.
//include all the required namespaces
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Text;
using System.Xml;
namespace Test
{
public class TestDataGrid : System.Windows.Forms
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.Windows.Forms.ComboBox cmbFunctionArea;
private DataTable dtblFunctionalArea;
private DataGrid dgdFunctionArea;
}
/// <summary>
/// public constructor
/// </summary>
public frmInitialShortListing()
{
//automatically generated by the VS Designer
//creates the object of the above designer variables
InitializeComponent();
PopulateGrid();
}
private void PopulateGrid()
{
//Declare and initialize local variables used
DataColumn dtCol = null;//Data Column variable
string[] arrstrFunctionalArea = null;//string array variable
System.Windows.Forms.ComboBox cmbFunctionArea; //combo box var
DataTable dtblFunctionalArea;//Data Table var
//Create the combo box object and set its properties
cmbFunctionArea = new ComboBox();
cmbFunctionArea.Cursor= System.Windows.Forms.Cursors.Arrow;
cmbFunctionArea.DropDownStyle=
System.Windows.Forms.ComboBoxStyle.DropDownList;
cmbFunctionArea.Dock = DockStyle.Fill;
// Event that will be fired when selected index in the combo box is
// changed
cmbFunctionArea.SelectionChangeCommitted += new
EventHandlercmbFunctionArea_SelectedIndexChanged);
//Create the String array object, initialize the array with the column
//names to be displayed
arrstrFunctionalArea = new string [3];
arrstrFunctionalArea[0] = "Functional Area";
arrstrFunctionalArea[1] = "Min";
arrstrFunctionalArea[2] = "Max";
//Create the Data Table object which will then be used to hold
//columns and rows
dtblFunctionalArea = new DataTable ("FunctionArea");
//Add the string array of columns to the DataColumn object
for(int i=0; i< 3;i++)
{
string str = arrstrFunctionalArea[i];
dtCol = new DataColumn(str);
dtCol.DataType = System.Type.GetType("System.String");
dtCol.DefaultValue = "";
dtblFunctionalArea.Columns.Add(dtCol);
}
//Add a Column with checkbox at last in the Grid
DataColumn dtcCheck = new DataColumn("IsMandatory");//create the data
//column object with the name
dtcCheck.DataType = System.Type.GetType("System.Boolean");//Set its
//data Type
dtcCheck.DefaultValue = false;//Set the default value
dtblFunctionalArea.Columns.Add(dtcCheck);//Add the above column to the
//Data Table
//Set the Data Grid Source as the Data Table createed above
dgdFunctionArea.DataSource = dtblFunctionalArea;
// set style property when first time the grid loads, next time onwards // it will maintain its property
if(!dgdFunctionArea.TableStyles.Contains("FunctionArea"))
{
//Create a DataGridTableStyle object
DataGridTableStyle dgdtblStyle = new DataGridTableStyle();
//Set its properties
dgdtblStyle.MappingName = dtblFunctionalArea.TableName;//its table name of dataset
dgdFunctionArea.TableStyles.Add(dgdtblStyle);
dgdtblStyle.RowHeadersVisible = false;
dgdtblStyle.HeaderBackColor = Color.LightSteelBlue;
dgdtblStyle.AllowSorting = false;
dgdtblStyle.HeaderBackColor = Color.FromArgb(8,36,107);
dgdtblStyle.RowHeadersVisible = false;
dgdtblStyle.HeaderForeColor = Color.White;
dgdtblStyle.HeaderFont = new System.Drawing.Font("Microsoft Sans Serif", 9F,
System.Drawing.FontStyle.Bold,
System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
dgdtblStyle.GridLineColor = Color.DarkGray;
dgdtblStyle.PreferredRowHeight = 22; dgdFunctionArea.BackgroundColor = Color.White;
//Take the columns in a GridColumnStylesCollection object and set //the // size of the individual columns
GridColumnStylesCollection colStyle;
colStyle = dgdFunctionArea.TableStyles[0].GridColumnStyles;
colStyle[0].Width = 100;
colStyle[1].Width = 50;
colStyle[2].Width = 50;
colStyle[3].Width = 80;
}
// To add the combo box dynamically to the data grid, you have to take
// the Text Box that is present (by default) in the column where u want // to add this combo box (here it is first column i.e. Functional
// Area).From the tablestyles of the data grid take the grid column
// styles of the column where you want to add the combo box
// respectively.
DataGridTextBoxColumn dgtb = (DataGridTextBoxColumn)dgdFunctionArea.TableStyles[0].GridColumnStyles[0];
//Add the combo box to the text box taken in the above step
dgtb.TextBox.Controls.Add (cmbFunctionArea);
Note:-//After these add the code to fill the details in the grid by //establishing
// connection to the server and writing necessary steps:
}//end of the class
}//end of the namespace
Combo Box Control Added to the Functional Area Column (For each Row) dynamically.
How to Add Check Boxes to a DataGrid
//call this below method after initialize component
private void PopulateShortlistGrid()
{
DataColumn dtcShortlist;
//Combo box control added as discussed above
cmbWorkflow = new ComboBox();
cmbWorkflow.Cursor = System.Windows.Forms.Cursors.Arrow;
cmbWorkflow.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
cmbWorkflow.Dock = DockStyle.Fill;
dtbShortlist = new DataTable("ShortList");
string strColumnName = null;
string []arraystringSearch = null;
arraystringSearch = new string[4];
arraystringSearch[1] = "Candidate Code";
arraystringSearch[2] = "Candidate Name";
arraystringSearch[3] = "Workflow";
//Adding a check box control in the first column of the data grid
//create a Data Column object with Column Name as "Select"
DataColumn dtcolCheck = new DataColumn("Select");
//Set the data type of the checkbox i.e. to Boolean
dtcolCheck.DataType = System.Type.GetType("System.Boolean");
//Set its default value as false
dtcolCheck.DefaultValue = false;
//add the above check box column to the data table
dtbShortlist.Columns.Add(dtcolCheck);
//Also add the other three columns i.e. Candidate Code, Candidate //Name and Workflow respectively
for(int intI=1; intI< 4;intI++)
{
strColumnName = arraystringSearch[intI];
dtcolShortlist = new DataColumn(strColumnName);
dtcolShortlist.DataType = System.Type.GetType("System.String");
dtbShortlist.Columns.Add(dtcolShortlist);
}
dgdShortList.DataSource = dtblshortlist;
}
Focusing a particular cell in the DataGrid
We have to focus on the TextBox Control that is present in each cell of the DataGrid created above to focus a particular cell in the grid created above. Follow the steps followed below to take the text box present in the grid cell which we want to focus:
//Bring the focus to the grid in which the cell is present (where you
want //the focus)
dgdLoad.Focus();
//Create a DataGrid Cell object and take the Cell by passing Row and //Column number respectively
DataGridCell dgcell = new DataGridCell(1,1); //here it is 2ndrow, 2nd Column
//Make the current cell of the grid as the cell you have taken above
//the cell where you need the focus to be
dgdLoad.CurrentCell = dgcell;
//To take the text Box of the cell where u want the focus to be take
//it from the Table Styles of the grid and in that the column style
//by passing the column number where youu wants the focus to be
DataGridTextBoxColumn dgtb = (DataGridTextBoxColumn)dgdLoad.TableStyles[0].GridColumnStyles[2];
//Focus on the text box i.e. in turn on cell where u need the focus
dgtb.TextBox.Focus();
Data Navigation Form with Unbound Controls
The form enables us to navigate through the records one at a time. We have used a combo box, two text boxes, and various command buttons in this application. The following is the run time view of the form shown initially. The data adapter is filled with data from the database and the combo box is populated with account numbers in ascending order when the form is loaded. The command buttons at the bottom of the form allows us to navigate through all the records one at a time. By using the first and last button respectively, we can instantly go to the first record and the last record. The current record number with respect to all the records is also displayed at the bottom of the page. These buttons are not the only means for navigating trough the records. By using the combo box we can also navigate through the records. The combo box enables us to select an account number and once its selected index is changed it will display all the details of that account number, basically the customer's name, and his balance.
The system provides not only navigating through the records it also enables us to;
- Add a new record to the database.
- Edit an existing record in the database.
- Delete an existing record in the database.
When a new record is added or when an existing record is edited, the UPDATE button is used to update the actual database. The CANCEL button can be used in order to discard the changes we were about to make. All other buttons but the "UPDATE" and the "CANCEL" button are disabled when a user clicks the ADD button to add a new record. This is because the other buttons have no significance with the system is in ADD mode. The customer is supposed to click the "UPDATE" button to update the actual database or the "CANCEL" button to discard the current changes when he is done filling the details of the new record.
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Data.OleDb;
namespace NavigatingRecordsUnbound
{
/// <summary>
/// Summary description for Form1.
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
private System.ComponentModel.Container components = null;
private System.Data.OleDb.OleDbConnection oleDbConnection1;
private System.Data.OleDb.OleDbDataAdapter oleDbDataAdapter1;
private System.Data.OleDb.OleDbCommandBuilder oleDbCommandBuilder1;
private DataSet sampleDset;
private string sqlStr;
private int currentRow;
private string opMode;
private string AccountNumber;
private System.Windows.Forms.ComboBox cbxAccountNumber;
private System.Windows.Forms.TextBox tbxName;
private System.Windows.Forms.TextBox tbxBalance;
private System.Windows.Forms.Label lblAccountNumber;
private System.Windows.Forms.Label lblName;
private System.Windows.Forms.Label lblBalance;
private System.Windows.Forms.Button btnFirst;
private System.Windows.Forms.Button btnPrevious;
private System.Windows.Forms.Button btnNext;
private System.Windows.Forms.Button btnLast;
private System.Windows.Forms.Button btnNew;
private System.Windows.Forms.Button btnEdit;
private System.Windows.Forms.Button btnDelete;
private System.Windows.Forms.Button btnUpdate;
private System.Windows.Forms.Label lblDisplay;
private System.Windows.Forms.Button btnCancel;
public Form1()
{
// Required for Windows Form Designer support
InitializeComponent();
// Attach event handlers to various buttons.
btnFirst.Click += new EventHandler(btnFirst_Click);
btnPrevious.Click += new EventHandler(btnPrevious_Click);
btnNext.Click += new EventHandler(btnNext_Click);
btnLast.Click += new EventHandler(btnLast_Click);
btnNew.Click += new EventHandler(btnNew_Click);
btnEdit.Click += new EventHandler(btnEdit_Click);
btnDelete.Click += new EventHandler(btnDelete_Click);
btnUpdate.Click += new EventHandler(btnUpdate_Click);
btnCancel.Click += new EventHandler(btnCancel_Click);
// Attach event handler to the Account Number combo box.
cbxAccountNumber.SelectedIndexChanged += new EventHandler(cbxAccountNumber_Changed);
loadData();
}
private void loadData()
{
string connStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\\Book Source Codes\\Navi\\bank_database.mdb";
oleDbConnection1 = new OleDbConnection(connStr);
oleDbConnection1.Open();
sampleDset = new DataSet();
sqlStr = "SELECT AccountNumber,CustomerName,AccountBalance "
+ "FROM bank ORDER BY AccountNumber";
oleDbDataAdapter1 = new OleDbDataAdapter(sqlStr, oleDbConnection1);
oleDbDataAdapter1.SelectCommand.CommandText = sqlStr;
oleDbCommandBuilder1 = new OleDbCommandBuilder(oleDbDataAdapter1);
oleDbDataAdapter1.Fill(sampleDset,"dtblBankAccounts");
currentRow = 0;
}
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.btnCancel = new System.Windows.Forms.Button();
this.lblBalance = new System.Windows.Forms.Label();
this.btnFirst = new System.Windows.Forms.Button();
this.cbxAccountNumber = new
System.Windows.Forms.ComboBox();
this.btnUpdate = new System.Windows.Forms.Button();
this.btnDelete = new System.Windows.Forms.Button();
this.btnNew = new System.Windows.Forms.Button();
this.btnPrevious = new System.Windows.Forms.Button();
this.lblName = new System.Windows.Forms.Label();
this.lblAccountNumber = new
System.Windows.Forms.Label();
this.btnNext = new System.Windows.Forms.Button();
this.tbxName = new System.Windows.Forms.TextBox();
this.tbxBalance = new System.Windows.Forms.TextBox();
this.btnLast = new System.Windows.Forms.Button();
this.btnEdit = new System.Windows.Forms.Button();
his.lblDisplay = new System.Windows.Forms.Label();
this.SuspendLayout();
// btnCancel
this.btnCancel.Location = new System.Drawing.Point(384, 16);
this.btnCancel.Name = "btnCancel";
this.btnCancel.TabIndex = 14;
this.btnCancel.Text = "Cancel";
//
// lblBalance
this.lblBalance.Location = new System.Drawing.Point(184, 112);
this.lblBalance.Name = "lblBalance";
this.lblBalance.Size = new System.Drawing.Size(80, 23);
this.lblBalance.TabIndex = 5;
this.lblBalance.Text = "Balance $";this.lblBalance.TextAlign = system.Drawing.ContentAlignment.MiddleRight;
//
// btnFirst
//
this.btnFirst.Location = new System.Drawing.Point(48, 192);
this.btnFirst.Name = "btnFirst";
this.btnFirst.TabIndex = 6;
this.btnFirst.Text = "|< First";
//
// cbxAccountNumber
//
this.cbxAccountNumber.DropDownWidth = 96;
this.cbxAccountNumber.Location = new
System.Drawing.Point(88, 72);
this.cbxAccountNumber.Name = "cbxAccountNumber";
this.cbxAccountNumber.Size = new System.Drawing.Size(96, 21);
this.cbxAccountNumber.TabIndex = 0;
//
// btnUpdate
//
this.btnUpdate.Location = new System.Drawing.Point(296, 16);
this.btnUpdate.Name = "btnUpdate";
this.btnUpdate.TabIndex = 13;
this.btnUpdate.Text = "Update";
// btnDelete
this.btnDelete.Location = new System.Drawing.Point(208, 16);
this.btnDelete.Name = "btnDelete";
this.btnDelete.TabIndex = 12;
this.btnDelete.Text = "Delete";
// btnNew//
this.btnNew.Location = new System.Drawing.Point(32, 16);
this.btnNew.Name = "btnNew";
this.btnNew.TabIndex = 10;
this.btnNew.Text = "New";
//
// btnPrevious
//
this.btnPrevious.Location = new System.Drawing.Point(160, 192);
this.btnPrevious.Name = "btnPrevious";
this.btnPrevious.TabIndex = 7;
this.btnPrevious.Text = "< Previous";
//
// lblName
//
this.lblName.Location = new System.Drawing.Point(200, 72);
this.lblName.Name = "lblName";
this.lblName.Size = new System.Drawing.Size(64, 23);
this.lblName.TabIndex = 4;
this.lblName.Text = "Name";
this.lblName.TextAlign =System.Drawing.ContentAlignment.MiddleRight;
//
// lblAccountNumber
this.lblAccountNumber.Location = new System.Drawing.Point(0, 72);
this.lblAccountNumber.Name = "lblAccountNumber";
this.lblAccountNumber.Size = new System.Drawing.Size(80, 23);
this.lblAccountNumber.TabIndex = 3;
this.lblAccountNumber.Text = "Acc Number";
this.lblAccountNumber.TextAlign =
System.Drawing.ContentAlignment.MiddleRight;
//
// btnNext
//
this.btnNext.Location = new System.Drawing.Point(264, 192);
this.btnNext.Name = "btnNext";
this.btnNext.TabIndex = 8;
this.btnNext.Text = "Next >";
// tbxName
//
this.tbxName.Location = new System.Drawing.Point(272, 72);
this.tbxName.Name = "tbxName";
this.tbxName.Size = new System.Drawing.Size(200, 20);
this.tbxName.TabIndex = 1;
this.tbxName.Text = "";
//
// tbxBalance
//
this.tbxBalance.Location = new System.Drawing.Point(272, 112);
this.tbxBalance.Name = "tbxBalance";
this.tbxBalance.TabIndex = 2;
this.tbxBalance.Text = "";
//
// btnLast
//
this.btnLast.Location = new System.Drawing.Point(368, 192);
this.btnLast.Name = "btnLast";
this.btnLast.TabIndex = 9;
this.btnLast.Text = "Last >|";
// btnEdit
//
this.btnEdit.Location = new System.Drawing.Point(120, 16);
this.btnEdit.Name = "btnEdit";
this.btnEdit.TabIndex = 11;this.btnEdit.Text = "Edit";
//
// lblDisplay
//
this.lblDisplay.Location = new System.Drawing.Point(136, 248);
this.lblDisplay.Name = "lblDisplay";
this.lblDisplay.Size = new System.Drawing.Size(232, 23);
this.lblDisplay.TabIndex = 15;
this.lblDisplay.TextAlign =
System.Drawing.ContentAlignment.MiddleCenter;
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.BackColor = System.Drawing.Color.Gainsboro;
this.ClientSize = new System.Drawing.Size(488, 309);
this.Controls.AddRange(new
System.Windows.Forms.Control[] {
this.lblDisplay,
this.btnCancel,
this.btnUpdate,
this.btnDelete,
this.btnEdit,
this.btnNew,
this.btnLast,
this.btnNext,
this.btnPrevious,
this.btnFirst,
this.lblBalance,
this.lblName,
this.lblAccountNumber,
this.tbxBalance,
this.tbxName,
this.cbxAccountNumber});
this.Name = "Form1";
this.Text = "Navigating One Bank Record At A Time";
this.Load += new System.EventHandler(this.Form1_Load);this.ResumeLayout(false);
}
#endregion
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void Form1_Load(object sender, System.EventArgs e)
{
pMode = "View";
lockControls();
populateAccountNumbers();
showData();
}
private void lockControls()
{
opMode = "View";
tbxName.ReadOnly = true;
tbxBalance.ReadOnly = true;
btnUpdate.Enabled = false;
btnCancel.Enabled = false;}
private void unlockControls()
{
tbxName.ReadOnly = false;
tbxBalance.ReadOnly = false;
btnUpdate.Enabled = true;
btnCancel.Enabled = true;
}
private void populateAccountNumbers()
{
for ( int i=0; i < sampleDset.Tables["dtblBankAccounts"].Rows.Count; i++)
cbxAccountNumber.Items.Add
(sampleDset.Tables["dtblBankAccounts"].Rows[i]["AccountNumber"].ToString());
}
private void showData()
{
cbxAccountNumber.Text =
sampleDset.Tables["dtblBankAccounts"].Rows[currentRow]["AccountNumber"].ToString();
tbxName.Text =
sampleDset.Tables["dtblBankAccounts"].Rows[currentRow]["CustomerName"].ToString();
tbxBalance.Text =
sampleDset.Tables["dtblBankAccounts"].Rows[currentRow]["AccountBalance"].ToString();
lblDisplay.Text = "Record " + (currentRow + 1).ToString() + " of " + sampleDset.Tables
"dtblBankAccounts"].Rows.Count.ToString();
}
private void btnFirst_Click(object source, System.EventArgs e)
{
currentRow = 0;
showData();
}
private void btnPrevious_Click(object source, System.EventArgs e)
{
if ( currentRow > 0 )
currentRow --;
showData();
}
private void btnNext_Click(object source, System.EventArgs e)
{
if ( currentRow < sampleDset.Tables["dtblBankAccounts"].Rows.Count -1 )
currentRow ++;
showData();
}
private void btnLast_Click(object source, System.EventArgs e)
{
currentRow = sampleDset.Tables["dtblBankAccounts"].Rows.Count -1;
showData();
}
private void btnUpdate_Click(object source, System.EventArgs e)
{
if (opMode == "New")
{
string newAccountNumber;
newAccountNumber = cbxAccountNumber.Text;
if ( !checkIfUnique(newAccountNumber) )
{
MessageBox.Show("Account Number already exists!");
cbxAccountNumber.Focus();
return;
}
DataRow newRow = sampleDset.Tables["dtblBankAccounts"].NewRow();
newRow["AccountNumber"] = cbxAccountNumber.Text;
newRow["CustomerName"] = tbxName.Text;
newRow["AccountBalance"] = double.Parse(tbxBalance.Text);
sampleDset.Tables["dtblBankAccounts"].Rows.Add(newRow);
cbxAccountNumber.Items.Add(cbxAccountNumber.Text);
oleDbDataAdapter1.Update(sampleDset,"dtblBankAccounts");
MessageBox.Show("Record successfully added!");
if (opMode == "Edit")
{
string newAccountNumber;
newAccountNumber = cbxAccountNumber.Text;
if ( !checkIfUnique(newAccountNumber) )
{
MessageBox.Show("Account Number already exists!");
cbxAccountNumber.Focus();
return;
}int index = cbxAccountNumber.Items.IndexOf(AccountNumber);
cbxAccountNumber.Items.RemoveAt(index);
cbxAccountNumber.Items.Insert(index, cbxAccountNumber.Text);
sampleDset.Tables["dtblBankAccounts"].Rows[currentRow]["AccountNumber"] = cbxAccountNumber.Text;
sampleDset.Tables["dtblBankAccounts"].Rows[currentRow]["CustomerName"] = tbxName.Text;
sampleDset.Tables["dtblBankAccounts"].Rows[currentRow]["AccountBalance"] = double.Parse
tbxBalance.Text);
oleDbDataAdapter1.Update(sampleDset,"dtblBankAccounts");
MessageBox.Show("Record Updated");
}
currentRow = 0;
lockControls();
showData();
btnNew.Enabled = true;
btnEdit.Enabled = true;
btnDelete.Enabled = true;
btnFirst.Enabled = true;
btnLast.Enabled = true;
btnPrevious.Enabled = true;
btnNext.Enabled = true;
btnNext.Focus();
}
private void btnEdit_Click(object source, System.EventArgs e)
{
urrentRow = cbxAccountNumber.SelectedIndex;
topMode = "Edit";
unlockControls();
btnCancel.Enabled = true;
btnUpdate.Enabled = true;
btnNew.Enabled = false;
btnEdit.Enabled = false;
btnDelete.Enabled = false;btnFirst.Enabled = false;btnLast.Enabled = false;
btnPrevious.Enabled = false;
btnNext.Enabled = false;
AccountNumber = cbxAccountNumber.Text;
cbxAccountNumber.Focus();}
private void btnNew_Click(object source, System.EventArgs e)
{
opMode = "New";
unlockControls();
bxAccountNumber.Text = "";
tbxName.Text = "";
tbxBalance.Text = "";
btnCancel.Enabled = true;
btnUpdate.Enabled = true;
btnNew.Enabled = false;
btnEdit.Enabled = false;
tnDelete.Enabled = false;
btnFirst.Enabled = false;
btnLast.Enabled = false;
btnPrevious.Enabled = false;
btnNext.Enabled = false;
lblDisplay.Text = "";
cbxAccountNumber.Focus();
}
private void btnCancel_Click(object source, System.EventArgs e)
{
lockControls();
showData();
btnNew.Enabled = true;
btnEdit.Enabled = true;
btnDelete.Enabled = true;
btnFirst.Enabled = true;
btnLast.Enabled = true;
btnPrevious.Enabled = true;
btnNext.Enabled = true;
btnNext.Focus();
}
private void btnDelete_Click(object source, System.EventArgs e)
{
int index = cbxAccountNumber.SelectedIndex;
sampleDset.Tables["dtblBankAccounts"].Rows[index].Delete();
oleDbDataAdapter1.Update(sampleDset,"dtblBankAccounts");
cbxAccountNumber.Items.RemoveAt(index);
currentRow = 0;
showData();
MessageBox.Show("Record successfully deleted!");
}
private void cbxAccountNumber_Changed(object source, System.EventArgs e)
{
if (opMode == "New" || opMode == "Edit")
{
MessageBox.Show("You cannot select an Account Number in this mode!");
cbxAccountNumber.Focus();
}
else
{
currentRow = cbxAccountNumber.SelectedIndex;
showData();
}
}
rivate bool checkIfUnique(string newAccountNumber)
{
string oldAccountNumber;
foreach ( DataRow r in sampleDset.Tables["dtblBankAccounts"].Rows )
{
oldAccountNumber = (string) r["AccountNumber"];
if ( newAccountNumber == oldAccountNumber )
return false;
}
return true;
}
}
Summary
In this article, we reviewed the DataGrid, the DataBind, and the most important server controls and techniques from ASP.NET and ADO.NET. We can use them most effectively when we take advantage of server controls. We discussed databinding expressions, server controls and then moved grid controls. Also we touched upon list and iterative controls. Data binding coverage does not end here, though, as it is too important a technology for building Web solutions with ADO.NET and ASP.NET.