本文实例为大家分享了C#实现鼠标裁剪图像的具体代码，供大家参考，具体内容如下
C#的图像裁剪很容易操作，这里给个实现的例子。
关键是需要处理鼠标的事件和一些更新
实现鼠标移动的代码.注意更新不要全部重画,只有选择矩形部分重画
private void Form1_MouseMove( object sender, MouseEventArgs e)
{
if (Track_move)
endpoint = new Point(e.X, e.Y);
else
{
return ;
}
rect1 = new Rectangle(stpoint.X, stpoint.Y, endpoint.X - stpoint.X, endpoint.Y - stpoint.Y);
Rectangle tempr = new Rectangle(rect1.X, rect1.Y, rect1.Width + 2, rect1.Height + 2);
this .Invalidate(tempr);
}
选择结束的处理代码.
private void Form1_MouseUp( object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left && Track_move== true )
{
Track_move = false ;
endpoint = new Point(e.X, e.Y);
rect1 = new Rectangle(stpoint.X, stpoint.Y, endpoint.X - stpoint.X, endpoint.Y - stpoint.Y);
Rectangle rectorg = new Rectangle(borg.X, borg.Y, image1.Width, image1.Height);
if (rect1.Width <= 0)
return ;
if (rect1.Height <= 0)
return ;
if (rectorg.Contains(rect1))
{
Rectangle rectadj = new Rectangle(rect1.X - borg.X, rect1.Y - borg.Y, rect1.Width, rect1.Height);
Bitmap cropimge = image1.Clone(rectadj, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
pictureBox2.Image = cropimge;
}
else
{
pictureBox2.Image = null ;
}
this .Invalidate();
}
}
程序的整个代码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace imageForms
{
static class Program
{
/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault( false );
Application.Run( new Form1());
}
}
public partial class Form1 : Form
{
private System.Windows.Forms.PictureBox pictureBox2;
private System.Windows.Forms.Label label1;
public Form1()
{
InitializeComponent();
}
private void pictureBox1_Click( object sender, EventArgs e)
{
}
private void Form1_Load( object sender, EventArgs e)
{
showimg();
}
Bitmap image1;
private void showimg()
{
int wd = 400;
int hg = 200;
int len = wd * hg * 3;
byte [] pdata = new byte [len];
for ( int i = 0; i < len; i++)
{
if (i > 3 * wd * (hg / 2))
{
pdata[i] = 255;
}
else
{
pdata[i] = 0;
}
}
try
{
image1 = new Bitmap(wd, hg, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
for ( int y = 0; y < hg; y++)
{
for ( int x = 0; x < wd; x++)
{
Color crr = Color.FromArgb(pdata[3 * wd * y + x], pdata[3 * wd * y + x], pdata[3 * wd * y + x]);
image1.SetPixel(x, y, crr);
}
}
// Set the PictureBox to display the image.
// pictureBox1.Image = image1;
}
catch (ArgumentException)
{
MessageBox.Show( "There was an error check data." );
}
}
Point stpoint,endpoint;
Rectangle rect1;
Point borg = new Point(20, 20);
protected override void OnPaint(PaintEventArgs e)
{
base .OnPaint(e);
e.Graphics.DrawImage(image1, borg);
if (rect1 != null )
{
e.Graphics.DrawRectangle( new Pen(Color.Red, 1), rect1);
}
}
private void Form1_MouseDown( object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
stpoint = new Point(e.X, e.Y);
Track_move = true ;
return ;
}
Track_move = false ;
}
private void Form1_MouseUp( object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left && Track_move== true )
{
Track_move = false ;
endpoint = new Point(e.X, e.Y);
rect1 = new Rectangle(stpoint.X, stpoint.Y, endpoint.X - stpoint.X, endpoint.Y - stpoint.Y);
Rectangle rectorg = new Rectangle(borg.X, borg.Y, image1.Width, image1.Height);
if (rect1.Width <= 0)
return ;
if (rect1.Height <= 0)
return ;
if (rectorg.Contains(rect1))
{
Rectangle rectadj = new Rectangle(rect1.X - borg.X, rect1.Y - borg.Y, rect1.Width, rect1.Height);
Bitmap cropimge = image1.Clone(rectadj, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
pictureBox2.Image = cropimge;
}
else
{
pictureBox2.Image = null ;
}
this .Invalidate();
}
}
bool Track_move= false ;
private void Form1_MouseMove( object sender, MouseEventArgs e)
{
if (Track_move)
endpoint = new Point(e.X, e.Y);
else
{
return ;
}
rect1 = new Rectangle(stpoint.X, stpoint.Y, endpoint.X - stpoint.X, endpoint.Y - stpoint.Y);
Rectangle tempr = new Rectangle(rect1.X, rect1.Y, rect1.Width + 2, rect1.Height + 2);
this .Invalidate(tempr);
}
private System.ComponentModel.IContainer components = null ;
private void InitializeComponent()
{
this .pictureBox2 = new System.Windows.Forms.PictureBox();
this .label1 = new System.Windows.Forms.Label();
((System.ComponentModel.ISupportInitialize)( this .pictureBox2)).BeginInit();
this .SuspendLayout();
//
// pictureBox2
//
this .pictureBox2.Location = new System.Drawing.Point(605, 103);
this .pictureBox2.Name = "pictureBox2" ;
this .pictureBox2.Size = new System.Drawing.Size(227, 173);
this .pictureBox2.TabIndex = 1;
this .pictureBox2.TabStop = false ;
//
// label1
//
this .label1.AutoSize = true ;
this .label1.Location = new System.Drawing.Point(602, 58);
this .label1.Name = "label1" ;
this .label1.Size = new System.Drawing.Size(127, 15);
this .label1.TabIndex = 2;
this .label1.Text = "鼠标左键选择裁剪" ;
//
// Form1
//
this .AutoScaleDimensions = new System.Drawing.SizeF(8F, 15F);
this .AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this .ClientSize = new System.Drawing.Size(844, 558);
this .Controls.Add( this .label1);
this .Controls.Add( this .pictureBox2);
this .Name = "Form1" ;
this .Text = "Form1" ;
this .Load += new System.EventHandler( this .Form1_Load);
this .MouseUp += new System.Windows.Forms.MouseEventHandler( this .Form1_MouseUp);
this .MouseDown += new System.Windows.Forms.MouseEventHandler( this .Form1_MouseDown);
this .MouseMove += new System.Windows.Forms.MouseEventHandler( this .Form1_MouseMove);
((System.ComponentModel.ISupportInitialize)( this .pictureBox2)).EndInit();
this .ResumeLayout( false );
this .PerformLayout();
}
protected override void Dispose( bool disposing)
{
if (disposing && (components != null ))
{
components.Dispose();
}
base .Dispose(disposing);
}
}
}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
原文链接：https://blog.csdn.net/s8848/article/details/46286513
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