c#中ListView控件加入ComboBox

很多项目中要用到ListView控件来呈现并编辑数据。为方便用户的输入,可在ListView控件中加入Combobox来提高其用户操作性。实现的效果图:

1.建立一用户控件,命名MyListView,继承自ListView控件。
直接贴出代码:

using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;

namespace InheritedListView
{
    /// <summary>
    /// Summary description for UserControl1.
    /// </summary>
    public class MyListView : System.Windows.Forms.ListView
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;

        public MyListView()
        {
            // This call is required by the Windows.Forms Form Designer.
            InitializeComponent();

            // TODO: Add any initialization after the InitForm call
        }

        /// <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 Component 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()
        {
            components = new System.ComponentModel.Container();
        }
        #endregion

        private const int WM_HSCROLL = 0x114;
        private const int WM_VSCROLL = 0x115;

        protected override void WndProc(ref Message msg)
        {
            // Look for the WM_VSCROLL or the WM_HSCROLL messages.
            if ((msg.Msg == WM_VSCROLL) || (msg.Msg == WM_HSCROLL))
            {
                // Move focus to the ListView to cause ComboBox to lose focus.
                this.Focus();
            }

            // Pass message to default handler.
            base.WndProc(ref msg);
        }
    }
}

2.建立一新的Windows应用程序项目。添加刚才创建的MyListView控件的引用。拖入MyListView控件和一ComboBox控件,令ComboBox Visible设为false。
直接贴出代码:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace WindowsApplication3
{

    public partial class Form1 : Form
    {
        private ListViewItem lvItem;
        public Form1()
        {
            InitializeComponent();
            // Add a few items to the combo box list.
            this.cbListViewCombo.Items.Add("NC");
            this.cbListViewCombo.Items.Add("WA");

            // Set view of ListView to Details.
            this.myListView1.View = View.Details;

            // Turn on full row select.
            this.myListView1.FullRowSelect = true;

            // Add data to the ListView.
            ColumnHeader columnheader;
            ListViewItem listviewitem;

            // Create sample ListView data.
            listviewitem = new ListViewItem("NC");
            listviewitem.SubItems.Add("North Carolina");
            this.myListView1.Items.Add(listviewitem);

            listviewitem = new ListViewItem("WA");
            listviewitem.SubItems.Add("Washington");
            this.myListView1.Items.Add(listviewitem);

            // Create column headers for the data.
            columnheader = new ColumnHeader();
            columnheader.Text = "State Abbr.";
            this.myListView1.Columns.Add(columnheader);

            columnheader = new ColumnHeader();
            columnheader.Text = "State";
            this.myListView1.Columns.Add(columnheader);

            // Loop through and size each column header to fit the column header text.
            foreach (ColumnHeader ch in this.myListView1.Columns)
            {
                ch.Width = -2;
            }

        }

        private void cbListViewCombo_SelectedValueChanged(object sender, EventArgs e)
        {
            // Set text of ListView item to match the ComboBox.
            lvItem.Text = this.cbListViewCombo.Text;

            // Hide the ComboBox.
            this.cbListViewCombo.Visible = false;

        }

        private void cbListViewCombo_SelectedIndexChanged(object sender, EventArgs e)
        {
            // Set text of ListView item to match the ComboBox.
            lvItem.Text = this.cbListViewCombo.Text;

            // Hide the ComboBox.
            this.cbListViewCombo.Visible = false;
        }

        private void cbListViewCombo_KeyPress(object sender, KeyPressEventArgs e)
        {
            // Verify that the user presses ESC.
            switch (e.KeyChar)
            {
                case (char)(int)Keys.Escape:
                    {
                        // Reset the original text value, and then hide the ComboBox.
                        this.cbListViewCombo.Text = lvItem.Text;
                        this.cbListViewCombo.Visible = false;
                        break;
                    }

                case (char)(int)Keys.Enter:
                    {
                        // Hide the ComboBox.
                        this.cbListViewCombo.Visible = false;
                        break;
                    }
            }

        }

        private void myListView1_MouseUp(object sender, MouseEventArgs e)
        {
            lvItem = this.myListView1.GetItemAt(e.X, e.Y);

            // Make sure that an item is clicked.
            if (lvItem != null)
            {

                // Get the bounds of the item that is clicked.
                Rectangle ClickedItem = lvItem.Bounds;

                //单击ListView第一列显示ComBoBox控件
                if (e.X > this.myListView1.Columns[0].Width)
                {
                    return;
                }
               
 // Verify that the column is completely scrolled off to the left.
                if ((ClickedItem.Left + this.myListView1.Columns[0].Width) < 0)
                {
                    // If the cell is out of view to the left, do nothing.
                    return;
                }
                
// Verify that the column is partially scrolled off to the left.
                else if (ClickedItem.Left < 0)
                {
                    // Determine if column extends beyond right side of ListView.
                    if ((ClickedItem.Left + this.myListView1.Columns[0].Width) > this.myListView1.Width)
                    {
                        // Set width of column to match width of ListView.
                        ClickedItem.Width = this.myListView1.Width;
                        ClickedItem.X = 0;
                    }
                    else
                    {
                        // Right side of cell is in view.
                        ClickedItem.Width = this.myListView1.Columns[0].Width + ClickedItem.Left;
                        ClickedItem.X = 2;
                    }
                }
                else if (this.myListView1.Columns[0].Width > this.myListView1.Width)
                {
                    ClickedItem.Width = this.myListView1.Width;
                }
                else
                {
                    ClickedItem.Width = this.myListView1.Columns[0].Width;
                    ClickedItem.X = 2;
                }

                // Adjust the top to account for the location of the ListView.
                ClickedItem.Y += this.myListView1.Top;
                ClickedItem.X += this.myListView1.Left;

                // Assign calculated bounds to the ComboBox.
                this.cbListViewCombo.Bounds = ClickedItem;

                // Set default text for ComboBox to match the item that is clicked.
                this.cbListViewCombo.Text = lvItem.Text;

                // Display the ComboBox, and make sure that it is on top with focus.
                this.cbListViewCombo.Visible = true;
                this.cbListViewCombo.BringToFront();
                this.cbListViewCombo.Focus();


            }
        }

        private void myListView1_Click(object sender, EventArgs e)
        {
            //this.myListView1.Select();
            this.cbListViewCombo.Visible = false;
        }
    }
}


posted on 2008-02-22 16:47  chunzhao.zhang  阅读(9108)  评论(0编辑  收藏  举报

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