Hi folks,
I am completely stuck on how to bind a KeyedCollection to a DataGridView. I can get it to work for the first record but then it has unpredictable results when I add subsequent records. It ends up throwing an exception at the line of code that opened the form, be that Form.ShowDialog() or Application.Run(new Form) - when the exception is thrown, it might be an InvalidOperationException or sometimes an OutOfRangeException.
I would love to find an example of how to do this, but I have not been able to find one.
Below I have included complete example of the code that causes the problem. The following instructions will have you replicate this:
Please do the following:
1. Create a new project using the Template "Empty Project"
2. Add a Class called Program.cs
3. open the class and delete everything in it.
4. Paste the contents of the Code Snippet below
5. Add references for:
System.Windows.Forms
System.Drawing
Run the program.
Click the add button
Click OK
Double click in a Cell of the DataGridView.
What am I doing wrong!?!?!?!
Begin Code
using System;
using System.Windows.Forms;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Text;
namespace Project1
{
/// <summary>
/// The SubForm which the user sees when he adds a record.
/// </summary>
public partial class frmAdd : Form
{
public GridViewRecord gvr { get; set; }
public frmAdd()
{
InitializeComponent();
this.gvr = new GridViewRecord();
tbFirstname.Text = gvr.FirstName;
tbSurname.Text = gvr.Surname;
tbOccupation.Text = gvr.Occupation;
}
private void btnOK_Click(object sender, EventArgs e)
{
gvr.FirstName = tbFirstname.Text;
gvr.Surname = tbSurname.Text;
gvr.Occupation = tbOccupation.Text;
this.Close();
}
}
/// <summary>
/// the Main Form presented to the user with all the data
/// </summary>
public partial class frmDataGridViewDemo : Form
{
private RecordCollection Items;
public frmDataGridViewDemo()
{
InitializeComponent();
this.Items = new RecordCollection();
bindingSource1.DataSource = this.Items;
dataGridView1.DataSource = bindingSource1;
}
private void btnAdd_Click(object sender, EventArgs e)
{
frmAdd Add = new frmAdd();
Add.ShowDialog();
this.Items.Add(Add.gvr);
}
}
/// <summary>
/// The individual records that are displayed in the datagridview
/// </summary>
public class GridViewRecord
{
public string FirstName { get; set; }
public string Surname { get; set; }
public string Occupation { get; set; }
public GridViewRecord()
{
this.FirstName = System.Guid.NewGuid().ToString();
this.Surname = System.Guid.NewGuid().ToString();
this.Occupation = System.Guid.NewGuid().ToString();
}
}
/// <summary>
/// The Keyed Collection with the BindingSource binds too.
/// </summary>
public class RecordCollection : KeyedCollection<string, GridViewRecord>
{
public RecordCollection() : base() { }
protected override string GetKeyForItem(GridViewRecord item)
{
return item.FirstName;
}
}
// ===================================================
// BEGIN WINDOWS Designer Code
// Everything below this line was built by the Windows
// designer IDE Conglobulator.
static class Program
{
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new frmDataGridViewDemo());
}
}
partial class frmAdd
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (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.tbFirstname = new System.Windows.Forms.TextBox();
this.tbSurname = new System.Windows.Forms.TextBox();
this.tbOccupation = new System.Windows.Forms.TextBox();
this.label1 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.label3 = new System.Windows.Forms.Label();
this.btnOK = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// tbFirstname
//
this.tbFirstname.Location = new System.Drawing.Point(79, 23);
this.tbFirstname.Name = "tbFirstname";
this.tbFirstname.Size = new System.Drawing.Size(184, 20);
this.tbFirstname.TabIndex = 0;
//
// tbSurname
//
this.tbSurname.Location = new System.Drawing.Point(79, 49);
this.tbSurname.Name = "tbSurname";
this.tbSurname.Size = new System.Drawing.Size(184, 20);
this.tbSurname.TabIndex = 1;
//
// tbOccupation
//
this.tbOccupation.Location = new System.Drawing.Point(79, 75);
this.tbOccupation.Name = "tbOccupation";
this.tbOccupation.Size = new System.Drawing.Size(184, 20);
this.tbOccupation.TabIndex = 2;
//
// label1
//
this.label1.AutoSize = true;
this.label1.Location = new System.Drawing.Point(16, 26);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(55, 13);
this.label1.TabIndex = 3;
this.label1.Text = "First name";
//
// label2
//
this.label2.AutoSize = true;
this.label2.Location = new System.Drawing.Point(16, 52);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(49, 13);
this.label2.TabIndex = 4;
this.label2.Text = "Surname";
//
// label3
//
this.label3.AutoSize = true;
this.label3.Location = new System.Drawing.Point(16, 78);
this.label3.Name = "label3";
this.label3.Size = new System.Drawing.Size(62, 13);
this.label3.TabIndex = 5;
this.label3.Text = "Occupation";
//
// btnOK
//
this.btnOK.Location = new System.Drawing.Point(165, 101);
this.btnOK.Name = "btnOK";
this.btnOK.Size = new System.Drawing.Size(98, 28);
this.btnOK.TabIndex = 6;
this.btnOK.Text = "OK";
this.btnOK.UseVisualStyleBackColor = true;
this.btnOK.Click += new System.EventHandler(this.btnOK_Click);
//
// frmAddForm
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(284, 141);
this.Controls.Add(this.btnOK);
this.Controls.Add(this.label3);
this.Controls.Add(this.label2);
this.Controls.Add(this.label1);
this.Controls.Add(this.tbOccupation);
this.Controls.Add(this.tbSurname);
this.Controls.Add(this.tbFirstname);
this.Name = "frmAddForm";
this.Text = "Add Record";
this.ResumeLayout(false);
this.PerformLayout();
}
#endregion
private System.Windows.Forms.TextBox tbFirstname;
private System.Windows.Forms.TextBox tbSurname;
private System.Windows.Forms.TextBox tbOccupation;
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.Label label3;
private System.Windows.Forms.Button btnOK;
}
partial class frmDataGridViewDemo
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (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.components = new System.ComponentModel.Container();
this.dataGridView1 = new System.Windows.Forms.DataGridView();
this.btnAdd = new System.Windows.Forms.Button();
this.bindingSource1 = new System.Windows.Forms.BindingSource(this.components);
((System.ComponentModel.ISupportInitialize)(this.dataGridView1)).BeginInit();
((System.ComponentModel.ISupportInitialize)(this.bindingSource1)).BeginInit();
this.SuspendLayout();
//
// dataGridView1
//
this.dataGridView1.AllowUserToOrderColumns = true;
this.dataGridView1.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize;
this.dataGridView1.Location = new System.Drawing.Point(15, 17);
this.dataGridView1.Name = "dataGridView1";
this.dataGridView1.Size = new System.Drawing.Size(488, 202);
this.dataGridView1.TabIndex = 0;
//
// btnAdd
//
this.btnAdd.Location = new System.Drawing.Point(423, 224);
this.btnAdd.Name = "btnAdd";
this.btnAdd.Size = new System.Drawing.Size(80, 28);
this.btnAdd.TabIndex = 1;
this.btnAdd.Text = "Add";
this.btnAdd.UseVisualStyleBackColor = true;
this.btnAdd.Click += new System.EventHandler(this.btnAdd_Click);
//
// frmDataGridViewDemo
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(522, 264);
this.Controls.Add(this.btnAdd);
this.Controls.Add(this.dataGridView1);
this.Name = "frmDataGridViewDemo";
this.Text = "DataGridView Demo";
((System.ComponentModel.ISupportInitialize)(this.dataGridView1)).EndInit();
((System.ComponentModel.ISupportInitialize)(this.bindingSource1)).EndInit();
this.ResumeLayout(false);
}
#endregion
private System.Windows.Forms.DataGridView dataGridView1;
private System.Windows.Forms.Button btnAdd;
private System.Windows.Forms.BindingSource bindingSource1;
}
}