基于C#实现设置桌面背景功能

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

    #region 调用API
    [DllImport("user32.dll", EntryPoint = "SystemParametersInfoA")]
    static extern Int32 SystemParametersInfo(Int32 uAction, Int32 uParam, string lpvparam, Int32 fuwinIni);
    private const int SPI_SETDESKWALLPAPER = 20;
    #endregion
    Form2 frm2;
    private void toolStripButton2_Click(object sender, EventArgs e)
    {
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            listView1.Items.Clear();
            string[] files = openFileDialog1.FileNames;
            string[] fileinfo = new string[3];
            for (int i = 0; i < files.Length; i++)
            {
                string path = files[i].ToString();
                string fileName = path.Substring(path.LastIndexOf("\\") + 1, path.Length - 1 - path.LastIndexOf("\\"));
                string filetype = fileName.Substring(fileName.LastIndexOf(".") + 1, fileName.Length - 1 - fileName.LastIndexOf("."));
                fileinfo[0] = fileName;
                fileinfo[1] = path;
                fileinfo[2] = filetype;
                ListViewItem lvi = new ListViewItem(fileinfo);
                listView1.Items.Add(lvi);
            }
        }
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        int x = this.Location.X;
        int y = this.Location.Y;
        frm2 = new Form2();
        frm2.x = x + this.Width;
        frm2.y = y;
        frm2.Hide();
        openFileDialog1.Filter = "支持的图片格式|*.jpeg;*.png;*.bmp;*.jpg";
    }

    private void toolStripButton1_Click(object sender, EventArgs e)
    {
        if (listView1.SelectedItems.Count > 0)
        {
            listView1.Items.RemoveAt(listView1.SelectedItems[0].Index);
        }
    }

    private void 添加ToolStripMenuItem_Click(object sender, EventArgs e)
    {
        toolStripButton2_Click(sender, e);
    }

    private void 删除ToolStripMenuItem_Click(object sender, EventArgs e)
    {
        toolStripButton1_Click(sender, e);
    }

    private void 清空ToolStripMenuItem_Click(object sender, EventArgs e)
    {
        listView1.Items.Clear();
    }

    private void 退出ToolStripMenuItem_Click(object sender, EventArgs e)
    {
        Application.Exit();
    }

    private void 设为桌面背景ToolStripMenuItem_Click(object sender, EventArgs e)
    {
        if (listView1.SelectedItems.Count > 0)
        {
            string FPath = listView1.SelectedItems[0].SubItems[1].Text;
            //获取指定图片的扩展名
            string SFileType = FPath.Substring(FPath.LastIndexOf(".") + 1, (FPath.Length - FPath.LastIndexOf(".") - 1));
            //将扩展名转换成小写
            SFileType = SFileType.ToLower();
            //获取文件名
            string SFileName = FPath.Substring(FPath.LastIndexOf("\\") + 1, (FPath.LastIndexOf(".") - FPath.LastIndexOf("\\") - 1));
            //如果图片的类型是bmp则调用API中的方法将其设置为桌面背景
            if (SFileType == "bmp")
            {
                SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, FPath, 1);
            }
            else
            {
                string SystemPath = Environment.SystemDirectory;//获取系统路径
                string path = SystemPath + "\\" + SFileName + ".bmp";
                FileInfo fi = new FileInfo(path);
                if (fi.Exists)
                {
                    fi.Delete();
                    PictureBox pb = new PictureBox();
                    pb.Image = Image.FromFile(FPath);
                    pb.Image.Save(SystemPath + "\\" + SFileName + ".bmp", ImageFormat.Bmp);
                }
                else
                {
                    PictureBox pb = new PictureBox();
                    pb.Image = Image.FromFile(FPath);
                    pb.Image.Save(SystemPath + "\\" + SFileName + ".bmp", ImageFormat.Bmp);
                }
                SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, path, 1);
            }
        }
    }
    
    private void Form1_LocationChanged(object sender, EventArgs e)
    {
        if (listView1.SelectedItems.Count > 0)
        {
            if (frm2 != null)
            {
                frm2.Close();
            }
            frm2 = new Form2();
            string path = listView1.SelectedItems[0].SubItems[1].Text;
            int x = this.Location.X;
            int y = this.Location.Y;
            frm2.x = x + this.Width;
            frm2.y = y;
            frm2.pictureBox1.Image = Image.FromFile(path);
            frm2.Show();
            this.Focus();
        }
        else
        {
            if (frm2 != null)
            {
                frm2.Close();
            }
            frm2 = new Form2();
            int x = this.Location.X;
            int y = this.Location.Y;
            frm2.x = x + this.Width;
            frm2.y = y;
            frm2.Hide();
            this.Focus();
        }
    }
    private void listView1_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (listView1.SelectedItems.Count > 0)
        {
            string path = listView1.SelectedItems[0].SubItems[1].Text;
            frm2.pictureBox1.Image = Image.FromFile(path);
            frm2.Show();
            this.Focus();
        }
    }
}

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.components = new System.ComponentModel.Container();
        this.toolStrip1 = new System.Windows.Forms.ToolStrip();
        this.toolStripButton2 = new System.Windows.Forms.ToolStripButton();
        this.toolStripButton1 = new System.Windows.Forms.ToolStripButton();
        this.listView1 = new System.Windows.Forms.ListView();
        this.columnHeader1 = new System.Windows.Forms.ColumnHeader();
        this.columnHeader2 = new System.Windows.Forms.ColumnHeader();
        this.columnHeader3 = new System.Windows.Forms.ColumnHeader();
        this.contextMenuStrip1 = new System.Windows.Forms.ContextMenuStrip(this.components);
        this.添加ToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
        this.删除ToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
        this.清空ToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
        this.toolStripSeparator1 = new System.Windows.Forms.ToolStripSeparator();
        this.设为桌面背景ToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
        this.退出ToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
        this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
        this.toolStrip1.SuspendLayout();
        this.contextMenuStrip1.SuspendLayout();
        this.SuspendLayout();
        // 
        // toolStrip1
        // 
        this.toolStrip1.GripStyle = System.Windows.Forms.ToolStripGripStyle.Hidden;
        this.toolStrip1.Items.AddRange(new System.Windows.Forms.ToolStripItem[] {
        this.toolStripButton2,
        this.toolStripButton1});
        this.toolStrip1.Location = new System.Drawing.Point(0, 0);
        this.toolStrip1.Name = "toolStrip1";
        this.toolStrip1.RenderMode = System.Windows.Forms.ToolStripRenderMode.System;
        this.toolStrip1.Size = new System.Drawing.Size(220, 25);
        this.toolStrip1.TabIndex = 0;
        this.toolStrip1.Text = "toolStrip1";
        // 
        // toolStripButton2
        // 
        this.toolStripButton2.Image = global::APIdesktop.Properties.Resources.图标__66_;
        this.toolStripButton2.ImageTransparentColor = System.Drawing.Color.Magenta;
        this.toolStripButton2.Name = "toolStripButton2";
        this.toolStripButton2.Size = new System.Drawing.Size(49, 22);
        this.toolStripButton2.Text = "增加";
        this.toolStripButton2.Click += new System.EventHandler(this.toolStripButton2_Click);
        // 
        // toolStripButton1
        // 
        this.toolStripButton1.Image = global::APIdesktop.Properties.Resources.图标__59_;
        this.toolStripButton1.ImageTransparentColor = System.Drawing.Color.Magenta;
        this.toolStripButton1.Name = "toolStripButton1";
        this.toolStripButton1.Size = new System.Drawing.Size(49, 22);
        this.toolStripButton1.Text = "删除";
        this.toolStripButton1.Click += new System.EventHandler(this.toolStripButton1_Click);
        // 
        // listView1
        // 
        this.listView1.BorderStyle = System.Windows.Forms.BorderStyle.None;
        this.listView1.Columns.AddRange(new System.Windows.Forms.ColumnHeader[] {
        this.columnHeader1,
        this.columnHeader2,
        this.columnHeader3});
        this.listView1.ContextMenuStrip = this.contextMenuStrip1;
        this.listView1.Dock = System.Windows.Forms.DockStyle.Fill;
        this.listView1.FullRowSelect = true;
        this.listView1.Location = new System.Drawing.Point(0, 25);
        this.listView1.MultiSelect = false;
        this.listView1.Name = "listView1";
        this.listView1.Size = new System.Drawing.Size(220, 338);
        this.listView1.TabIndex = 1;
        this.listView1.UseCompatibleStateImageBehavior = false;
        this.listView1.View = System.Windows.Forms.View.Details;
        this.listView1.SelectedIndexChanged += new System.EventHandler(this.listView1_SelectedIndexChanged);
        // 
        // columnHeader1
        // 
        this.columnHeader1.Text = "名称";
        this.columnHeader1.Width = 80;
        // 
        // columnHeader2
        // 
        this.columnHeader2.Text = "路径";
        this.columnHeader2.Width = 80;
        // 
        // columnHeader3
        // 
        this.columnHeader3.Text = "类型";
        // 
        // contextMenuStrip1
        // 
        this.contextMenuStrip1.Items.AddRange(new System.Windows.Forms.ToolStripItem[] {
        this.添加ToolStripMenuItem,
        this.删除ToolStripMenuItem,
        this.清空ToolStripMenuItem,
        this.toolStripSeparator1,
        this.设为桌面背景ToolStripMenuItem,
        this.退出ToolStripMenuItem});
        this.contextMenuStrip1.Name = "contextMenuStrip1";
        this.contextMenuStrip1.RenderMode = System.Windows.Forms.ToolStripRenderMode.Professional;
        this.contextMenuStrip1.Size = new System.Drawing.Size(143, 120);
        // 
        // 添加ToolStripMenuItem
        // 
        this.添加ToolStripMenuItem.Image = global::APIdesktop.Properties.Resources.图标__199_;
        this.添加ToolStripMenuItem.Name = "添加ToolStripMenuItem";
        this.添加ToolStripMenuItem.Size = new System.Drawing.Size(142, 22);
        this.添加ToolStripMenuItem.Text = "添加";
        this.添加ToolStripMenuItem.Click += new System.EventHandler(this.添加ToolStripMenuItem_Click);
        // 
        // 删除ToolStripMenuItem
        // 
        this.删除ToolStripMenuItem.Image = global::APIdesktop.Properties.Resources.图标__96_;
        this.删除ToolStripMenuItem.Name = "删除ToolStripMenuItem";
        this.删除ToolStripMenuItem.Size = new System.Drawing.Size(142, 22);
        this.删除ToolStripMenuItem.Text = "删除";
        this.删除ToolStripMenuItem.Click += new System.EventHandler(this.删除ToolStripMenuItem_Click);
        // 
        // 清空ToolStripMenuItem
        // 
        this.清空ToolStripMenuItem.Image = global::APIdesktop.Properties.Resources.图标__190_;
        this.清空ToolStripMenuItem.Name = "清空ToolStripMenuItem";
        this.清空ToolStripMenuItem.Size = new System.Drawing.Size(142, 22);
        this.清空ToolStripMenuItem.Text = "清空";
        this.清空ToolStripMenuItem.Click += new System.EventHandler(this.清空ToolStripMenuItem_Click);
        // 
        // toolStripSeparator1
        // 
        this.toolStripSeparator1.Name = "toolStripSeparator1";
        this.toolStripSeparator1.Size = new System.Drawing.Size(139, 6);
        // 
        // 设为桌面背景ToolStripMenuItem
        // 
        this.设为桌面背景ToolStripMenuItem.Image = global::APIdesktop.Properties.Resources.图标__22_;
        this.设为桌面背景ToolStripMenuItem.Name = "设为桌面背景ToolStripMenuItem";
        this.设为桌面背景ToolStripMenuItem.Size = new System.Drawing.Size(142, 22);
        this.设为桌面背景ToolStripMenuItem.Text = "设为桌面背景";
        this.设为桌面背景ToolStripMenuItem.Click += new System.EventHandler(this.设为桌面背景ToolStripMenuItem_Click);
        // 
        // 退出ToolStripMenuItem
        // 
        this.退出ToolStripMenuItem.Image = global::APIdesktop.Properties.Resources.图标__8_;
        this.退出ToolStripMenuItem.Name = "退出ToolStripMenuItem";
        this.退出ToolStripMenuItem.Size = new System.Drawing.Size(142, 22);
        this.退出ToolStripMenuItem.Text = "退出";
        this.退出ToolStripMenuItem.Click += new System.EventHandler(this.退出ToolStripMenuItem_Click);
        // 
        // openFileDialog1
        // 
        this.openFileDialog1.Multiselect = true;
        // 
        // Form1
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.ClientSize = new System.Drawing.Size(220, 363);
        this.Controls.Add(this.listView1);
        this.Controls.Add(this.toolStrip1);
        this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle;
        this.MaximizeBox = false;
        this.MinimizeBox = false;
        this.Name = "Form1";
        this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
        this.Text = "设置桌面背景";
        this.Load += new System.EventHandler(this.Form1_Load);
        this.LocationChanged += new System.EventHandler(this.Form1_LocationChanged);
        this.toolStrip1.ResumeLayout(false);
        this.toolStrip1.PerformLayout();
        this.contextMenuStrip1.ResumeLayout(false);
        this.ResumeLayout(false);
        this.PerformLayout();

    }

    #endregion

    private System.Windows.Forms.ToolStrip toolStrip1;
    private System.Windows.Forms.ListView listView1;
    private System.Windows.Forms.ToolStripButton toolStripButton2;
    private System.Windows.Forms.ToolStripButton toolStripButton1;
    private System.Windows.Forms.ColumnHeader columnHeader1;
    private System.Windows.Forms.ColumnHeader columnHeader2;
    private System.Windows.Forms.ColumnHeader columnHeader3;
    private System.Windows.Forms.OpenFileDialog openFileDialog1;
    private System.Windows.Forms.ContextMenuStrip contextMenuStrip1;
    private System.Windows.Forms.ToolStripMenuItem 添加ToolStripMenuItem;
    private System.Windows.Forms.ToolStripMenuItem 删除ToolStripMenuItem;
    private System.Windows.Forms.ToolStripMenuItem 清空ToolStripMenuItem;
    private System.Windows.Forms.ToolStripSeparator toolStripSeparator1;
    private System.Windows.Forms.ToolStripMenuItem 设为桌面背景ToolStripMenuItem;
    private System.Windows.Forms.ToolStripMenuItem 退出ToolStripMenuItem;
}

public partial class Form2 : Form
{
    public Form2()
    {
        InitializeComponent();
    }
    public int x;
    public int y;
    private void pictureBox1_Click(object sender, EventArgs e)
    {

    }

    private void Form2_Load(object sender, EventArgs e)
    {
        this.Location = new Point(x,y);
    }
}

partial class Form2
{
    /// <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.pictureBox1 = new System.Windows.Forms.PictureBox();
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).BeginInit();
        this.SuspendLayout();
        // 
        // pictureBox1
        // 
        this.pictureBox1.BackColor = System.Drawing.Color.Black;
        this.pictureBox1.Location = new System.Drawing.Point(23, 24);
        this.pictureBox1.Name = "pictureBox1";
        this.pictureBox1.Size = new System.Drawing.Size(349, 348);
        this.pictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.Zoom;
        this.pictureBox1.TabIndex = 0;
        this.pictureBox1.TabStop = false;
        this.pictureBox1.Click += new System.EventHandler(this.pictureBox1_Click);
        // 
        // Form2
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.BackColor = System.Drawing.Color.White;
        this.BackgroundImage = global::APIdesktop.Properties.Resources.bg2;
        this.ClientSize = new System.Drawing.Size(395, 395);
        this.Controls.Add(this.pictureBox1);
        this.DoubleBuffered = true;
        this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
        this.Name = "Form2";
        this.ShowIcon = false;
        this.ShowInTaskbar = false;
        this.Text = "Form2";
        this.TransparencyKey = System.Drawing.Color.DarkGray;
        this.Load += new System.EventHandler(this.Form2_Load);
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).EndInit();
        this.ResumeLayout(false);

    }

    #endregion

    public System.Windows.Forms.PictureBox pictureBox1;

}