基于C#实现屏幕桌面截图

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        [DllImport("user32.dll", EntryPoint = "GetSystemMetrics")]
        private static extern int GetSystemMetrics(int mVal);
        private void button1_Click(object sender, EventArgs e)
        {
            Bitmap _Source = new Bitmap(GetSystemMetrics(0), GetSystemMetrics(1));
            using (Graphics g = Graphics.FromImage(_Source))
            {
                g.CopyFromScreen(0, 0, 0, 0, _Source.Size);
                g.Dispose();
            }
            pictureBox1.Image = _Source;
        }
    }

partial class Form1
{
    /// <summary>
    /// 必需的设计器变量。
    /// </summary>
    private System.ComponentModel.IContainer components = null;

    /// <summary>
    /// 清理所有正在使用的资源。
    /// </summary>
    /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
    protected override void Dispose(bool disposing)
    {
        if (disposing && (components != null))
        {
            components.Dispose();
        }
        base.Dispose(disposing);
    }

    #region Windows 窗体设计器生成的代码

    /// <summary>
    /// 设计器支持所需的方法 - 不要
    /// 使用代码编辑器修改此方法的内容。
    /// </summary>
    private void InitializeComponent()
    {
        this.button1 = new System.Windows.Forms.Button();
        this.pictureBox1 = new System.Windows.Forms.PictureBox();
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).BeginInit();
        this.SuspendLayout();
        // 
        // button1
        // 
        this.button1.Location = new System.Drawing.Point(24, 12);
        this.button1.Name = "button1";
        this.button1.Size = new System.Drawing.Size(75, 23);
        this.button1.TabIndex = 0;
        this.button1.Text = "抓取桌面";
        this.button1.UseVisualStyleBackColor = true;
        this.button1.Click += new System.EventHandler(this.button1_Click);
        // 
        // pictureBox1
        // 
        this.pictureBox1.Location = new System.Drawing.Point(105, 12);
        this.pictureBox1.Name = "pictureBox1";
        this.pictureBox1.Size = new System.Drawing.Size(515, 306);
        this.pictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.Zoom;
        this.pictureBox1.TabIndex = 1;
        this.pictureBox1.TabStop = false;
        // 
        // Form1
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.ClientSize = new System.Drawing.Size(648, 330);
        this.Controls.Add(this.pictureBox1);
        this.Controls.Add(this.button1);
        this.Name = "Form1";
        this.Text = "Form1";
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).EndInit();
        this.ResumeLayout(false);

    }

    #endregion

    private System.Windows.Forms.Button button1;
    private System.Windows.Forms.PictureBox pictureBox1;
}

  public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }


        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            Image memory = new Bitmap(300,200);
            Graphics g = Graphics.FromImage(memory);
            g.CopyFromScreen(0,0, 0, 0, new Size(300,200));
            pictureBox1.Image = memory;
        }
    }

partial class Form1
{
    /// <summary>
    /// 必需的设计器变量。
    /// </summary>
    private System.ComponentModel.IContainer components = null;

    /// <summary>
    /// 清理所有正在使用的资源。
    /// </summary>
    /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
    protected override void Dispose(bool disposing)
    {
        if (disposing && (components != null))
        {
            components.Dispose();
        }
        base.Dispose(disposing);
    }

    #region Windows 窗体设计器生成的代码

    /// <summary>
    /// 设计器支持所需的方法 - 不要
    /// 使用代码编辑器修改此方法的内容。
    /// </summary>
    private void InitializeComponent()
    {
        this.pictureBox1 = new System.Windows.Forms.PictureBox();
        this.button1 = new System.Windows.Forms.Button();
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).BeginInit();
        this.SuspendLayout();
        // 
        // pictureBox1
        // 
        this.pictureBox1.Location = new System.Drawing.Point(12, 12);
        this.pictureBox1.Name = "pictureBox1";
        this.pictureBox1.Size = new System.Drawing.Size(309, 200);
        this.pictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.Zoom;
        this.pictureBox1.TabIndex = 0;
        this.pictureBox1.TabStop = false;
        // 
        // button1
        // 
        this.button1.Location = new System.Drawing.Point(327, 32);
        this.button1.Name = "button1";
        this.button1.Size = new System.Drawing.Size(131, 23);
        this.button1.TabIndex = 1;
        this.button1.Text = "抓取左上角的图片";
        this.button1.UseVisualStyleBackColor = true;
        this.button1.Click += new System.EventHandler(this.button1_Click);
        // 
        // Form1
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.ClientSize = new System.Drawing.Size(470, 225);
        this.Controls.Add(this.button1);
        this.Controls.Add(this.pictureBox1);
        this.Name = "Form1";
        this.Text = "Form1";
        this.Load += new System.EventHandler(this.Form1_Load);
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).EndInit();
        this.ResumeLayout(false);

    }

    #endregion

    private System.Windows.Forms.PictureBox pictureBox1;
    private System.Windows.Forms.Button button1;
}