ComBobox、TextBox控件扩展（Enable=false,灰色）
Code
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
namespace pcd.Tools
{
public class TextBoxEnable : System.Windows.Forms.TextBox
{
构造函数#region 构造函数
public TextBoxEnable()
{
this.BorderStyle = BorderStyle.FixedSingle;
}
#endregion
//重写OnEnabledChanged
protected override void OnEnabledChanged(EventArgs e)
{
if (Enabled == false)
{
SetStyle(ControlStyles.UserPaint, true);
}
else
{
SetStyle(ControlStyles.UserPaint, false);
this.Font = new Font(“宋体“, 9F);
}
base.OnEnabledChanged(e);
}
//重写OnPaint
protected override void OnPaint(PaintEventArgs pe)
{
base.OnPaint(pe);
if (Enabled == false)
{
pe.Graphics.FillRectangle(new SolidBrush(SystemColors.ControlLight),
pe.ClipRectangle);
//文字描画
float x = 0, y = 0;
Size s = pe.Graphics.MeasureString(Text, Font).ToSize();
if (this.TextAlign == HorizontalAlignment.Left)
{
x = 1;//←
}
else if (this.TextAlign == HorizontalAlignment.Right)
{
x = Width – s.Width;//→
}
else if (this.TextAlign == HorizontalAlignment.Center)
{
x = (Width – s.Width) / 2;
}
y = 5.5F;
if (this.Multiline)
pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, new RectangleF(x, y, this.Width, this.Height));
else
pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, new RectangleF(x, y, 1000, this.Height));//单行是，width可以设置成无限大。
pe.Graphics.DrawRectangle(new Pen(Color.Black, 2), new Rectangle(0, 0, this.Width, this.Height));//pe.ClipRectangle
}
}
}
}
Code
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
using System.ComponentModel;
namespace pcd.Tools
{
// 2.声明一个委托。
public delegate void ReadOnlyEventHandler(object sender, ReadOnlyEventArgs args);
public class ComboboxReadOnly : ComboBox
{
ReadOnly#region ReadOnly
private bool _ReadOnle;
[Bindable(true),
Category(“Data“),
DefaultValue(false),
Description(“获取或者设置是否只读“),
DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public bool ReadOnly
{
get
{
return this._ReadOnle;
}
set
{
ReadOnlyEventArgs roea = new ReadOnlyEventArgs(this._ReadOnle != value);
this._ReadOnle = value;
OnReadOnlyChanged(roea);
}
}
#endregion
定义事件readonlychanged#region 定义事件readonlychanged
// 3.定义事件
[
Description(“在更改控件的只读状态时发生。“),
DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public event ReadOnlyEventHandler readonlychanged;
// 4.事件发生后，通知其他对象的方法
//这个方法是受保护的虚方法
protected virtual void OnReadOnlyChanged(ReadOnlyEventArgs args)
{
if (ReadOnly)
{
SetStyle(ControlStyles.UserPaint, true);
}
else
{
SetStyle(ControlStyles.UserPaint, false);
this.Font = new Font(“宋体“, 9F);
}
if (readonlychanged != null)
{
readonlychanged(this, args);
}
//***
Invalidate();//强制一个控件触发onPaint事件
}
#endregion
构造函数#region 构造函数
public ComboboxReadOnly()
{
this.DropDownStyle = ComboBoxStyle.DropDownList;
this.TabStop = false;
}
#endregion
override#region override
//重写WndProc
protected override void WndProc(ref Message m)
{
if (this._ReadOnle && (m.Msg == 0xa1 || m.Msg == 0x201 || m.Msg == 0x203))
{
return;
}
base.WndProc(ref m);
}
//重写OnPaint
protected override void OnPaint(PaintEventArgs pe)
{
base.OnPaint(pe);
if (this.ReadOnly)
{
pe.Graphics.FillRectangle(new SolidBrush(SystemColors.ControlLight),
pe.ClipRectangle);
//文字描画
int x = 0, y = 0;
Size s = pe.Graphics.MeasureString(Text, Font).ToSize();
y = (Height – s.Height) / 2;
x = 1;//←
pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, x, y);
pe.Graphics.DrawRectangle(new Pen(Color.Black, 2), new Rectangle(0, 0, this.Width, this.Height));//pe.ClipRectangle
}
}
重写OnEnabledChanged也可以。不过用readonly更好#region 重写OnEnabledChanged也可以。不过用readonly更好
//重写OnEnabledChanged
//protected override void OnEnabledChanged(EventArgs e)
//{
// if (Enabled == false)
// {
// SetStyle(ControlStyles.UserPaint, true);
// }
// else
// {
// SetStyle(ControlStyles.UserPaint, false);
// }
// base.OnEnabledChanged(e);
//}
//重写OnPaint
//protected override void OnPaint(PaintEventArgs pe)
//{
//base.OnPaint(pe);
//if (Enabled == false)
//{
// pe.Graphics.FillRectangle(new SolidBrush(SystemColors.ControlLight),
// pe.ClipRectangle);
// //文字描画
// int x = 0, y = 0;
// Size s = pe.Graphics.MeasureString(Text, Font).ToSize();
// // x = Width – s.Width;//→
// y = (Height – s.Height) / 2;
// x = 1;//←
// pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, x, y);
// pe.Graphics.DrawRectangle(new Pen(Color.Black, 2), pe.ClipRectangle);
//}
// }
#endregion
#endregion
}
1.定义一个携带事件信息的类。#region 1.定义一个携带事件信息的类。
public class ReadOnlyEventArgs : EventArgs
{
private bool readvalue;
public bool ReadValue
{
get { return readvalue; }
}
public ReadOnlyEventArgs(bool readonlyvalue)
{
this.readvalue = readonlyvalue;
}
}
#endregion
}
注：
1.ComBoboxReadOnly控件主要是在ComBobox基础上扩展了ReadOnly属性、OnReadOnlyChanged事件。
2.通过这两个控件可以熟悉控件开发，掌握自定义控件属性、事件的处理。
3.控件源码如下：
TextBoxEnable.cs
Code
using System;using System.Collections.Generic;using System.Text;using System.Windows.Forms;using System.Drawing;namespace pcd.Tools{ public class TextBoxEnable : System.Windows.Forms.TextBox { 构造函数#region 构造函数 public TextBoxEnable() { this.BorderStyle = BorderStyle.FixedSingle; } #endregion //重写OnEnabledChanged protected override void OnEnabledChanged(EventArgs e) { if (Enabled == false) { SetStyle(ControlStyles.UserPaint, true); } else { SetStyle(ControlStyles.UserPaint, false); this.Font = new Font(“宋体“, 9F); } base.OnEnabledChanged(e); } //重写OnPaint protected override void OnPaint(PaintEventArgs pe) { base.OnPaint(pe); if (Enabled == false) { pe.Graphics.FillRectangle(new SolidBrush(SystemColors.ControlLight), pe.ClipRectangle); //文字描画 float x = 0, y = 0; Size s = pe.Graphics.MeasureString(Text, Font).ToSize(); if (this.TextAlign == HorizontalAlignment.Left) { x = 1;//← } else if (this.TextAlign == HorizontalAlignment.Right) { x = Width – s.Width;//→ } else if (this.TextAlign == HorizontalAlignment.Center) { x = (Width – s.Width) / 2; } y = 5.5F; if (this.Multiline) pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, new RectangleF(x, y, this.Width, this.Height)); else pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, new RectangleF(x, y, 1000, this.Height));//单行是，width可以设置成无限大。 pe.Graphics.DrawRectangle(new Pen(Color.Black, 2), new Rectangle(0, 0, this.Width, this.Height));//pe.ClipRectangle } } }}
ComBoboxReadOnly.cs
Code
using System;using System.Collections.Generic;using System.Text;using System.Windows.Forms;using System.Drawing;using System.ComponentModel;namespace pcd.Tools{ // 2.声明一个委托。 public delegate void ReadOnlyEventHandler(object sender, ReadOnlyEventArgs args); public class ComboboxReadOnly : ComboBox { ReadOnly#region ReadOnly private bool _ReadOnle; [Bindable(true), Category(“Data“), DefaultValue(false), Description(“获取或者设置是否只读“), DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)] public bool ReadOnly { get { return this._ReadOnle; } set { ReadOnlyEventArgs roea = new ReadOnlyEventArgs(this._ReadOnle != value); this._ReadOnle = value; OnReadOnlyChanged(roea); } } #endregion 定义事件readonlychanged#region 定义事件readonlychanged // 3.定义事件 [ Description(“在更改控件的只读状态时发生。“), DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)] public event ReadOnlyEventHandler readonlychanged; // 4.事件发生后，通知其他对象的方法 //这个方法是受保护的虚方法 protected virtual void OnReadOnlyChanged(ReadOnlyEventArgs args) { if (ReadOnly) { SetStyle(ControlStyles.UserPaint, true); } else { SetStyle(ControlStyles.UserPaint, false); this.Font = new Font(“宋体“, 9F); } if (readonlychanged != null) { readonlychanged(this, args); } //*** Invalidate();//强制一个控件触发onPaint事件 } #endregion 构造函数#region 构造函数 public ComboboxReadOnly() { this.DropDownStyle = ComboBoxStyle.DropDownList; this.TabStop = false; } #endregion override#region override //重写WndProc protected override void WndProc(ref Message m) { if (this._ReadOnle && (m.Msg == 0xa1 || m.Msg == 0x201 || m.Msg == 0x203)) { return; } base.WndProc(ref m); } //重写OnPaint protected override void OnPaint(PaintEventArgs pe) { base.OnPaint(pe); if (this.ReadOnly) { pe.Graphics.FillRectangle(new SolidBrush(SystemColors.ControlLight), pe.ClipRectangle); //文字描画 int x = 0, y = 0; Size s = pe.Graphics.MeasureString(Text, Font).ToSize(); y = (Height – s.Height) / 2; x = 1;//← pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, x, y); pe.Graphics.DrawRectangle(new Pen(Color.Black, 2), new Rectangle(0, 0, this.Width, this.Height));//pe.ClipRectangle } } 重写OnEnabledChanged也可以。不过用readonly更好#region 重写OnEnabledChanged也可以。不过用readonly更好 //重写OnEnabledChanged //protected override void OnEnabledChanged(EventArgs e) //{ // if (Enabled == false) // { // SetStyle(ControlStyles.UserPaint, true); // } // else // { // SetStyle(ControlStyles.UserPaint, false); // } // base.OnEnabledChanged(e); //} //重写OnPaint //protected override void OnPaint(PaintEventArgs pe) //{ //base.OnPaint(pe); //if (Enabled == false) //{ // pe.Graphics.FillRectangle(new SolidBrush(SystemColors.ControlLight), // pe.ClipRectangle); // //文字描画 // int x = 0, y = 0; // Size s = pe.Graphics.MeasureString(Text, Font).ToSize(); // // x = Width – s.Width;//→ // y = (Height – s.Height) / 2; // x = 1;//← // pe.Graphics.DrawString(this.Text, this.Font, Brushes.Black, x, y); // pe.Graphics.DrawRectangle(new Pen(Color.Black, 2), pe.ClipRectangle); //} // } #endregion #endregion } 1.定义一个携带事件信息的类。#region 1.定义一个携带事件信息的类。 public class ReadOnlyEventArgs : EventArgs { private bool readvalue; public bool ReadValue { get { return readvalue; } } public ReadOnlyEventArgs(bool readonlyvalue) { this.readvalue = readonlyvalue; } } #endregion}
转载于:https://www.cnblogs.com/jdmei520/archive/2009/01/05/1369344.html