写一个小程序，程序运行后背景是白屏（满屏），然后可以将图片导入到白屏，在白屏里对图片可以伸缩，移动

Question

想写一个小程序，程序运行后背景是白屏（满屏），然后可以将图片导入到白屏，在白屏里对图片可以伸缩，移动没有思路，给思路，代码都非常感谢。 VC, C#代码都可以

Answer 1

以下代码,你新建个项目Test,修改Form1为TestForm 
然后打开TestForm.Designer.cs和TestForm.cs
替换里面的代码即可.
鼠标滚动,可以放大缩小.鼠标可以拖动图片.如果满意就给100分吧.
//TestForm.Designer.cs
namespace Test
{
    partial class TestForm
    {
        /// <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.Pic_Image = new System.Windows.Forms.PictureBox();
            this.Btn_Open = new System.Windows.Forms.Button();
            this.Ofd_ImageFile = new System.Windows.Forms.OpenFileDialog();
            this.Hsl_Scaling = new System.Windows.Forms.HScrollBar();
            this.Pan_Main = new System.Windows.Forms.Panel();
            this.Lab_ImagePath = new System.Windows.Forms.Label();
            this.Txt_Path = new System.Windows.Forms.TextBox();
            ((System.ComponentModel.ISupportInitialize)(this.Pic_Image)).BeginInit();
            this.Pan_Main.SuspendLayout();
            this.SuspendLayout();
            // 
            // Pic_Image
            // 
            this.Pic_Image.Anchor = System.Windows.Forms.AnchorStyles.None;
            this.Pic_Image.Cursor = System.Windows.Forms.Cursors.SizeAll;
            this.Pic_Image.Location = new System.Drawing.Point(0, 0);
            this.Pic_Image.Name = "Pic_Image";
            this.Pic_Image.Size = new System.Drawing.Size(406, 261);
            this.Pic_Image.SizeMode = System.Windows.Forms.PictureBoxSizeMode.CenterImage;
            this.Pic_Image.TabIndex = 0;
            this.Pic_Image.TabStop = false;
            this.Pic_Image.MouseMove += new System.Windows.Forms.MouseEventHandler(this.Pic_Image_MouseMove);
            this.Pic_Image.MouseDown += new System.Windows.Forms.MouseEventHandler(this.Pic_Image_MouseDown);
            this.Pic_Image.MouseUp += new System.Windows.Forms.MouseEventHandler(this.Pic_Image_MouseUp);
            // 
            // Btn_Open
            // 
            this.Btn_Open.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
            this.Btn_Open.Location = new System.Drawing.Point(343, 10);
            this.Btn_Open.Name = "Btn_Open";
            this.Btn_Open.Size = new System.Drawing.Size(75, 23);
            this.Btn_Open.TabIndex = 4;
            this.Btn_Open.Text = "打开";
            this.Btn_Open.UseVisualStyleBackColor = true;
            this.Btn_Open.Click += new System.EventHandler(this.Btn_Open_Click);
            // 
            // Ofd_ImageFile
            // 
            this.Ofd_ImageFile.FileName = "*.*";
            this.Ofd_ImageFile.Filter = "BMP 图像|*.bmp|JPEG 图像|*.jpg;*.jpeg|GIF 图像|*.gif|PNG 图像|*.png|所有图像文件|*.*";
            // 
            // Hsl_Scaling
            // 
            this.Hsl_Scaling.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.Hsl_Scaling.Location = new System.Drawing.Point(12, 304);
            this.Hsl_Scaling.Maximum = 16;
            this.Hsl_Scaling.Minimum = 1;
            this.Hsl_Scaling.Name = "Hsl_Scaling";
            this.Hsl_Scaling.Size = new System.Drawing.Size(406, 17);
            this.Hsl_Scaling.TabIndex = 5;
            this.Hsl_Scaling.Value = 1;
            this.Hsl_Scaling.ValueChanged += new System.EventHandler(this.Hsl_Scaling_ValueChanged);
            // 
            // Pan_Main
            // 
            this.Pan_Main.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.Pan_Main.Controls.Add(this.Pic_Image);
            this.Pan_Main.Location = new System.Drawing.Point(12, 40);
            this.Pan_Main.Name = "Pan_Main";
            this.Pan_Main.Size = new System.Drawing.Size(406, 261);
            this.Pan_Main.TabIndex = 7;
            // 
            // Lab_ImagePath
            // 
            this.Lab_ImagePath.AutoSize = true;
            this.Lab_ImagePath.Location = new System.Drawing.Point(12, 15);
            this.Lab_ImagePath.Name = "Lab_ImagePath";
            this.Lab_ImagePath.Size = new System.Drawing.Size(59, 12);
            this.Lab_ImagePath.TabIndex = 8;
            this.Lab_ImagePath.Text = "图片路径:";
            // 
            // Txt_Path
            // 
            this.Txt_Path.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.Txt_Path.Location = new System.Drawing.Point(77, 12);
            this.Txt_Path.Name = "Txt_Path";
            this.Txt_Path.Size = new System.Drawing.Size(260, 21);
            this.Txt_Path.TabIndex = 9;
            // 
            // TestForm
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(430, 337);
            this.Controls.Add(this.Txt_Path);
            this.Controls.Add(this.Lab_ImagePath);
            this.Controls.Add(this.Hsl_Scaling);
            this.Controls.Add(this.Btn_Open);
            this.Controls.Add(this.Pan_Main);
            this.MinimumSize = new System.Drawing.Size(446, 375);
            this.Name = "TestForm";
            this.Text = "TestForm";
            this.Load += new System.EventHandler(this.TestForm_Load);
            ((System.ComponentModel.ISupportInitialize)(this.Pic_Image)).EndInit();
            this.Pan_Main.ResumeLayout(false);
            this.ResumeLayout(false);
            this.PerformLayout();        }        #endregion        private System.Windows.Forms.PictureBox Pic_Image;
        private System.Windows.Forms.Button Btn_Open;
        private System.Windows.Forms.OpenFileDialog Ofd_ImageFile;
        private System.Windows.Forms.HScrollBar Hsl_Scaling;
        private System.Windows.Forms.Panel Pan_Main;
        private System.Windows.Forms.Label Lab_ImagePath;
        private System.Windows.Forms.TextBox Txt_Path;
    }
}

Answer 2

//TestForm.csusing System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;namespace Test
{
    public partial class TestForm : Form
    {
        public TestForm()
        {
            InitializeComponent();
        }        private Image Src = null;        bool M_Down = false;
        Point M_Location = Point.Empty;        private void Btn_Open_Click(object sender, EventArgs e)
        {
            if (this.Ofd_ImageFile.ShowDialog(this) == DialogResult.OK)
            {
                this.Txt_Path.Text = this.Ofd_ImageFile.FileName;
                this.Pic_Image.Image = Src = Image.FromFile(this.Ofd_ImageFile.FileName);
            }
        }        private void TestForm_Load(object sender, EventArgs e)
        {
            this.MouseWheel += new MouseEventHandler(TestForm_MouseWheel);
        }        void TestForm_MouseWheel(object sender, MouseEventArgs e)
        {
            //获取光标位置
            Point mousePoint = this.PointToScreen(new Point(e.X, e.Y));
            //判断是否在panel内
            if (this.Pan_Main.RectangleToScreen(Pan_Main.DisplayRectangle).Contains(mousePoint))
            {
                //滚动
                int value = this.Hsl_Scaling.Value + e.Delta / 120;
                if (value <= this.Hsl_Scaling.Maximum && value >= this.Hsl_Scaling.Minimum)
                {
                    this.Hsl_Scaling.Value = value;
                }
            }
        }        private void Hsl_Scaling_ValueChanged(object sender, EventArgs e)
        {
            if (Src != null)
            {
                Size s = this.Pic_Image.Size;                this.Pic_Image.Size = new Size(Src.Width * this.Hsl_Scaling.Value, Src.Height * this.Hsl_Scaling.Value);
                Bitmap bmp = new Bitmap(this.Pic_Image.Width, this.Pic_Image.Height);
                using (Graphics g = Graphics.FromImage(bmp))
                {
                    g.InterpolationMode = InterpolationMode.NearestNeighbor;
                    g.DrawImage(Src, 0, 0, bmp.Width, bmp.Height);
                }
                this.Pic_Image.Image = (Image)bmp.Clone();                if (s.Width > this.Pic_Image.Size.Width)
                {
                    //缩小
                    this.Pic_Image.Location = new Point(this.Pic_Image.Left + (s.Width - this.Pic_Image.Size.Width) / 2, this.Pic_Image.Top + (s.Height - this.Pic_Image.Size.Height) / 2);
                }
                else if (s.Width < this.Pic_Image.Size.Width)
                {
                    //放大
                    this.Pic_Image.Location = new Point(this.Pic_Image.Left - (this.Pic_Image.Size.Width - s.Width) / 2, this.Pic_Image.Top - (this.Pic_Image.Size.Height - s.Height) / 2);
                }
            }
        }        private void Btn_Src_Click(object sender, EventArgs e)
        {
            if (this.Hsl_Scaling.Value == 1)
            {
                Hsl_Scaling_ValueChanged(sender, e);
            }
            else
            {
                this.Hsl_Scaling.Value = 1;
            }
        }        private void Pic_Image_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                M_Down = true;
                this.M_Location = new Point(e.X, e.Y);
            }
        }        private void Pic_Image_MouseUp(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                M_Down = false;
            }
        }        private void Pic_Image_MouseMove(object sender, MouseEventArgs e)
        {
            if (M_Down && e.Button == MouseButtons.Left)
            {
                if (M_Down)
                {
                    this.Pic_Image.Location = new Point(this.Pic_Image.Location.X + e.X - M_Location.X, this.Pic_Image.Location.Y + e.Y - M_Location.Y);
                }
            }
        }
    }
}

Answer 3

谢谢sjzlxd， 你的程序对我很有帮助，我想对我有的帮助远超100分。还想请教下就是怎么在保持背景不变的情况下调整图片的尺寸？ 导入多个图片的时候不要覆盖以前的图片？就像Word一样，可以导入多个图片，可以随意改变图片的形状。

Answer 4

如果想导入多个 不覆盖 就需要多个pic控件了. 这个说白了就是分层了. 跟Photoshop的图片 层 是一个道理.