using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;namespace DrapDrop1
{
public partial class Form1 : Form
{
private System.Windows.Forms.ListBox ListDragSource; private System.Windows.Forms.ListBox ListDragTarget; private System.Windows.Forms.CheckBox UseCustomCursorsCheck; private System.Windows.Forms.Label DropLocationLabel; private int indexOfItemUnderMouseToDrag; private int indexOfItemUnderMouseToDrop; private System.Drawing.Rectangle dragBoxFromMouseDown; private System.Drawing.Point screenOffset; private System.Windows.Forms.Cursor MyNoDropCursor; private System.Windows.Forms.Cursor MyNormalCursor; public Form1() { InitializeComponent();
} private void ListDragSource_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e) { // Get the index of the item the mouse is below. indexOfItemUnderMouseToDrag = ListDragSource.IndexFromPoint(e.X, e.Y); if (indexOfItemUnderMouseToDrag != ListBox.NoMatches) { // Remember the point where the mouse down occurred. The DragSize indicates // the size that the mouse can move before a drag event should be started. Size dragSize = SystemInformation.DragSize; // Create a rectangle using the DragSize, with the mouse position being // at the center of the rectangle. dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2), e.Y - (dragSize.Height / 2)), dragSize); } else // Reset the rectangle if the mouse is not over an item in the ListBox. dragBoxFromMouseDown = Rectangle.Empty; } private void ListDragSource_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e) { // Reset the drag rectangle when the mouse button is raised. dragBoxFromMouseDown = Rectangle.Empty; } private void ListDragSource_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e) { if ((e.Button & MouseButtons.Left) == MouseButtons.Left) { // If the mouse moves outside the rectangle, start the drag. if (dragBoxFromMouseDown != Rectangle.Empty && !dragBoxFromMouseDown.Contains(e.X, e.Y)) { // Create custom cursors for the drag-and-drop operation. try { MyNormalCursor = new Cursor("3dwarro.cur"); MyNoDropCursor = new Cursor("3dwno.cur"); } catch { // An error occurred while attempting to load the cursors, so use // standard cursors. UseCustomCursorsCheck.Checked = false; } finally { // The screenOffset is used to account for any desktop bands // that may be at the top or left side of the screen when // determining when to cancel the drag drop operation. screenOffset = SystemInformation.WorkingArea.Location; // Proceed with the drag-and-drop, passing in the list item. DragDropEffects dropEffect = ListDragSource.DoDragDrop(ListDragSource.Items[indexOfItemUnderMouseToDrag], DragDropEffects.All | DragDropEffects.Link); // If the drag operation was a move then remove the item. if (dropEffect == DragDropEffects.Move) { ListDragSource.Items.RemoveAt(indexOfItemUnderMouseToDrag); // Selects the previous item in the list as long as the list has an item. if (indexOfItemUnderMouseToDrag > 0) ListDragSource.SelectedIndex = indexOfItemUnderMouseToDrag - 1; else if (ListDragSource.Items.Count > 0) // Selects the first item. ListDragSource.SelectedIndex = 0; } // Dispose of the cursors since they are no longer needed. if (MyNormalCursor != null) MyNormalCursor.Dispose(); if (MyNoDropCursor != null) MyNoDropCursor.Dispose(); } } } } private void ListDragSource_GiveFeedback(object sender, System.Windows.Forms.GiveFeedbackEventArgs e) { // Use custom cursors if the check box is checked. if (UseCustomCursorsCheck.Checked) { // Sets the custom cursor based upon the effect. e.UseDefaultCursors = false; if ((e.Effect & DragDropEffects.Move) == DragDropEffects.Move) Cursor.Current = MyNormalCursor; else Cursor.Current = MyNoDropCursor; } } private void ListDragTarget_DragOver(object sender, System.Windows.Forms.DragEventArgs e) { // Determine whether string data exists in the drop data. If not, then // the drop effect reflects that the drop cannot occur. if (!e.Data.GetDataPresent(typeof(System.String))) { e.Effect = DragDropEffects.None; DropLocationLabel.Text = "None - no string data."; return; } // Set the effect based upon the KeyState. if ((e.KeyState & (8 + 32)) == (8 + 32) && (e.AllowedEffect & DragDropEffects.Link) == DragDropEffects.Link) { // KeyState 8 + 32 = CTL + ALT // Link drag-and-drop effect. e.Effect = DragDropEffects.Link; } else if ((e.KeyState & 32) == 32 && (e.AllowedEffect & DragDropEffects.Link) == DragDropEffects.Link) { // ALT KeyState for link. e.Effect = DragDropEffects.Link; } else if ((e.KeyState & 4) == 4 && (e.AllowedEffect & DragDropEffects.Move) == DragDropEffects.Move) { // SHIFT KeyState for move. e.Effect = DragDropEffects.Move; } else if ((e.KeyState & 8) == 8 && (e.AllowedEffect & DragDropEffects.Copy) == DragDropEffects.Copy) { // CTL KeyState for copy. e.Effect = DragDropEffects.Copy; } else if ((e.AllowedEffect & DragDropEffects.Move) == DragDropEffects.Move) { // By default, the drop action should be move, if allowed. e.Effect = DragDropEffects.Move; } else e.Effect = DragDropEffects.None; // Get the index of the item the mouse is below. // The mouse locations are relative to the screen, so they must be // converted to client coordinates. indexOfItemUnderMouseToDrop = ListDragTarget.IndexFromPoint(ListDragTarget.PointToClient(new Point(e.X, e.Y))); // Updates the label text. if (indexOfItemUnderMouseToDrop != ListBox.NoMatches) { DropLocationLabel.Text = "Drops before item #" + (indexOfItemUnderMouseToDrop + 1); } else DropLocationLabel.Text = "Drops at the end."; } private void ListDragTarget_DragDrop(object sender, System.Windows.Forms.DragEventArgs e) { // Ensure that the list item index is contained in the data. if (e.Data.GetDataPresent(typeof(System.String))) { Object item = (object)e.Data.GetData(typeof(System.String)); // Perform drag-and-drop, depending upon the effect. if (e.Effect == DragDropEffects.Copy || e.Effect == DragDropEffects.Move) { // Insert the item. if (indexOfItemUnderMouseToDrop != ListBox.NoMatches) ListDragTarget.Items.Insert(indexOfItemUnderMouseToDrop, item); else ListDragTarget.Items.Add(item); } } // Reset the label text. DropLocationLabel.Text = "None"; } private void ListDragSource_QueryContinueDrag(object sender, System.Windows.Forms.QueryContinueDragEventArgs e) { // Cancel the drag if the mouse moves off the form. ListBox lb = sender as ListBox; if (lb != null) { Form f = lb.FindForm(); // Cancel the drag if the mouse moves off the form. The screenOffset // takes into account any desktop bands that may be at the top or left // side of the screen. if (((Control.MousePosition.X - screenOffset.X) < f.DesktopBounds.Left) || ((Control.MousePosition.X - screenOffset.X) > f.DesktopBounds.Right) || ((Control.MousePosition.Y - screenOffset.Y) < f.DesktopBounds.Top) || ((Control.MousePosition.Y - screenOffset.Y) > f.DesktopBounds.Bottom)) { e.Action = DragAction.Cancel; } } } private void ListDragTarget_DragEnter(object sender, System.Windows.Forms.DragEventArgs e) { // Reset the label text. DropLocationLabel.Text = "None"; } private void ListDragTarget_DragLeave(object sender, System.EventArgs e) { // Reset the label text. DropLocationLabel.Text = "None"; } }
}5 查看控件實時屬性值
using System;using System.Collections;using System.ComponentModel;using System.Drawing;using System.Reflection;using System.Windows.Forms;namespace SystemInfoBrowser{ public class SystemInfoBrowserForm : System.Windows.Forms.Form { private System.Windows.Forms.ListBox listBox1; private System.Windows.Forms.TextBox textBox1; public SystemInfoBrowserForm() { this.SuspendLayout(); InitForm(); // Add each property of the SystemInformation class to the list box. Type t = typeof(System.Windows.Forms.SystemInformation); PropertyInfo[] pi = t.GetProperties(); for (int i = 0; i < pi.Length; i++) listBox1.Items.Add(pi[i].Name); textBox1.Text = "The SystemInformation class has " + pi.Length.ToString() + " properties. "; // Configure the list item selected handler for the list box to invoke a // method that displays the value of each property. listBox1.SelectedIndexChanged += new EventHandler(listBox1_SelectedIndexChanged); this.ResumeLayout(false); } private void listBox1_SelectedIndexChanged(object sender, EventArgs e) { // Return if no list item is selected. if (listBox1.SelectedIndex == -1) return; // Get the property name from the list item. string propname = listBox1.Text; if (propname == "PowerStatus") { // Cycle and display the values of each property of the PowerStatus property. textBox1.Text += " The value of the PowerStatus property is:"; Type t = typeof(System.Windows.Forms.PowerStatus); PropertyInfo[] pi = t.GetProperties(); for (int i = 0; i < pi.Length; i++) { object propval = pi[i].GetValue(SystemInformation.PowerStatus, null); textBox1.Text += " PowerStatus." + pi[i].Name + " is: " + propval.ToString(); } } else { // Display the value of the selected property of the SystemInformation type. Type t = typeof(System.Windows.Forms.SystemInformation); PropertyInfo[] pi = t.GetProperties(); PropertyInfo prop = null; for (int i = 0; i < pi.Length; i++) if (pi[i].Name == propname) { prop = pi[i]; break; } object propval = prop.GetValue(null, null); textBox1.Text += " The value of the " + propname + " property is: " + propval.ToString(); } } private void InitForm() { // Initialize the form settings this.listBox1 = new System.Windows.Forms.ListBox(); this.textBox1 = new System.Windows.Forms.TextBox(); this.listBox1.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) | System.Windows.Forms.AnchorStyles.Left) | System.Windows.Forms.AnchorStyles.Right))); this.listBox1.Location = new System.Drawing.Point(8, 16); this.listBox1.Size = new System.Drawing.Size(172, 496); this.listBox1.TabIndex = 0; this.textBox1.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) | System.Windows.Forms.AnchorStyles.Right))); this.textBox1.Location = new System.Drawing.Point(188, 16); this.textBox1.Multiline = true; this.textBox1.ScrollBars = System.Windows.Forms.ScrollBars.Vertical; this.textBox1.Size = new System.Drawing.Size(420, 496); this.textBox1.TabIndex = 1; this.ClientSize = new System.Drawing.Size(616, 525); this.Controls.Add(this.textBox1); this.Controls.Add(this.listBox1); this.Text = "Select a SystemInformation property to get the value of"; } [STAThread] static void Main() { Application.Run(new SystemInfoBrowserForm()); } }}6 datagridview VirtualMode 模式
using System;using System.Collections.Generic;using System.Windows.Forms;namespace datagridview_virtualMode{ public class Form1 : Form { private DataGridView dataGridView1 = new DataGridView(); // Declare an ArrayList to serve as the data store. private System.Collections.ArrayList customers = new System.Collections.ArrayList(); // Declare a Customer object to store data for a row being edited. private Customer customerInEdit; // Declare a variable to store the index of a row being edited. // A value of -1 indicates that there is no row currently in edit. private int rowInEdit = -1; // Declare a variable to indicate the commit scope. // Set this value to false to use cell-level commit scope. private bool rowScopeCommit = true; [STAThreadAttribute()] public static void Main() { Application.Run(new Form1()); } public Form1() { // Initialize the form. this.dataGridView1.Dock = DockStyle.Fill; this.Controls.Add(this.dataGridView1); this.Load += new EventHandler(Form1_Load); this.Text = "DataGridView virtual-mode demo (row-level commit scope)"; } private void Form1_Load(object sender, EventArgs e) { // Enable virtual mode. this.dataGridView1.VirtualMode = true; // Connect the virtual-mode events to event handlers. this.dataGridView1.CellValueNeeded += new DataGridViewCellValueEventHandler(dataGridView1_CellValueNeeded); this.dataGridView1.CellValuePushed += new DataGridViewCellValueEventHandler(dataGridView1_CellValuePushed); this.dataGridView1.NewRowNeeded += new DataGridViewRowEventHandler(dataGridView1_NewRowNeeded); this.dataGridView1.RowValidated += new DataGridViewCellEventHandler(dataGridView1_RowValidated); this.dataGridView1.RowDirtyStateNeeded += new QuestionEventHandler(dataGridView1_RowDirtyStateNeeded); this.dataGridView1.CancelRowEdit += new QuestionEventHandler(dataGridView1_CancelRowEdit); this.dataGridView1.UserDeletingRow += new DataGridViewRowCancelEventHandler(dataGridView1_UserDeletingRow); // Add columns to the DataGridView. DataGridViewTextBoxColumn companyNameColumn = new DataGridViewTextBoxColumn(); companyNameColumn.HeaderText = "Company Name"; companyNameColumn.Name = "Company Name"; DataGridViewTextBoxColumn contactNameColumn = new DataGridViewTextBoxColumn(); contactNameColumn.HeaderText = "Contact Name"; contactNameColumn.Name = "Contact Name"; this.dataGridView1.Columns.Add(companyNameColumn); this.dataGridView1.Columns.Add(contactNameColumn); this.dataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells; // Add some sample entries to the data store. this.customers.Add(new Customer( "Bon app'", "Laurence Lebihan")); this.customers.Add(new Customer( "Bottom-Dollar Markets", "Elizabeth Lincoln")); this.customers.Add(new Customer( "B's Beverages", "Victoria Ashworth")); // Set the row count, including the row for new records. this.dataGridView1.RowCount = 4; } private void dataGridView1_CellValueNeeded(object sender, System.Windows.Forms.DataGridViewCellValueEventArgs e) { // If this is the row for new records, no values are needed. if (e.RowIndex == this.dataGridView1.RowCount - 1) return; Customer customerTmp = null; // Store a reference to the Customer object for the row being painted. if (e.RowIndex == rowInEdit) { customerTmp = this.customerInEdit; } else { customerTmp = (Customer)this.customers[e.RowIndex]; } // Set the cell value to paint using the Customer object retrieved. switch (this.dataGridView1.Columns[e.ColumnIndex].Name) { case "Company Name": e.Value = customerTmp.CompanyName; break; case "Contact Name": e.Value = customerTmp.ContactName; break; } } private void dataGridView1_CellValuePushed(object sender, System.Windows.Forms.DataGridViewCellValueEventArgs e) { Customer customerTmp = null; // Store a reference to the Customer object for the row being edited. if (e.RowIndex < this.customers.Count) { // If the user is editing a new row, create a new Customer object. if (this.customerInEdit == null) { this.customerInEdit = new Customer( ((Customer)this.customers[e.RowIndex]).CompanyName, ((Customer)this.customers[e.RowIndex]).ContactName); } customerTmp = this.customerInEdit; this.rowInEdit = e.RowIndex; } else { customerTmp = this.customerInEdit; } // Set the appropriate Customer property to the cell value entered. String newValue = e.Value as String; switch (this.dataGridView1.Columns[e.ColumnIndex].Name) { case "Company Name": customerTmp.CompanyName = newValue; break; case "Contact Name": customerTmp.ContactName = newValue; break; } } private void dataGridView1_NewRowNeeded(object sender, System.Windows.Forms.DataGridViewRowEventArgs e) { // Create a new Customer object when the user edits // the row for new records. this.customerInEdit = new Customer(); this.rowInEdit = this.dataGridView1.Rows.Count - 1; } private void dataGridView1_RowValidated(object sender, System.Windows.Forms.DataGridViewCellEventArgs e) { // Save row changes if any were made and release the edited // Customer object if there is one. if (e.RowIndex >= this.customers.Count && e.RowIndex != this.dataGridView1.Rows.Count - 1) { // Add the new Customer object to the data store. this.customers.Add(this.customerInEdit); this.customerInEdit = null; this.rowInEdit = -1; } else if (this.customerInEdit != null && e.RowIndex < this.customers.Count) { // Save the modified Customer object in the data store. this.customers[e.RowIndex] = this.customerInEdit; this.customerInEdit = null; this.rowInEdit = -1; } else if (this.dataGridView1.ContainsFocus) { this.customerInEdit = null; this.rowInEdit = -1; } } private void dataGridView1_RowDirtyStateNeeded(object sender, System.Windows.Forms.QuestionEventArgs e) { if (!rowScopeCommit) { // In cell-level commit scope, indicate whether the value // of the current cell has been modified. e.Response = this.dataGridView1.IsCurrentCellDirty; } } private void dataGridView1_CancelRowEdit(object sender, System.Windows.Forms.QuestionEventArgs e) { if (this.rowInEdit == this.dataGridView1.Rows.Count - 2 && this.rowInEdit == this.customers.Count) { // If the user has canceled the edit of a newly created row, // replace the corresponding Customer object with a new, empty one. this.customerInEdit = new Customer(); } else { // If the user has canceled the edit of an existing row, // release the corresponding Customer object. this.customerInEdit = null; this.rowInEdit = -1; } } private void dataGridView1_UserDeletingRow(object sender, System.Windows.Forms.DataGridViewRowCancelEventArgs e) { if (e.Row.Index < this.customers.Count) { // If the user has deleted an existing row, remove the // corresponding Customer object from the data store. this.customers.RemoveAt(e.Row.Index); } if (e.Row.Index == this.rowInEdit) { // If the user has deleted a newly created row, release // the corresponding Customer object. this.rowInEdit = -1; this.customerInEdit = null; } } } public class Customer { private String companyNameValue; private String contactNameValue; public Customer() { // Leave fields empty. } public Customer(String companyName, String contactName) { companyNameValue = companyName; contactNameValue = contactName; } public String CompanyName { get { return companyNameValue; } set { companyNameValue = value; } } public String ContactName { get { return contactNameValue; } set { contactNameValue = value; } } }}