c# winform查询时怎么弹出请等待的图片

c# winform查询时如何弹出请等待的图片
c# winform查询时如何弹出请等待的图片，查询结束后小时的效果。
请高数指点。

我用的显示隐藏Visible但是不行，只是在查询结束后才显示

[解决办法]
Form1.cs

C# code

    public class Form1 : Form    {        public Form1()        {            InitializeComponent();        }        private void button1_Click(object sender, EventArgs e)        {            Form2 frm = new Form2();            frm.OnDoSomething += new EventHandler(frm_OnDoSomething);            frm.ShowDialog();            MessageBox.Show("查询完成");        }        void frm_OnDoSomething(object sender, EventArgs e)        {            //在此处写入你需要查询的操作            System.Threading.Thread.Sleep(3000);        }        /// <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.SuspendLayout();            //             // button1            //             this.button1.Location = new System.Drawing.Point(309, 172);            this.button1.Name = "button1";            this.button1.Size = new System.Drawing.Size(75, 23);            this.button1.TabIndex = 0;            this.button1.Text = "button1";            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(658, 419);            this.Controls.Add(this.button1);            this.Name = "Form1";            this.Text = "Form1";            this.ResumeLayout(false);        }        #endregion        private System.Windows.Forms.Button button1;    }
[解决办法]
thread th=new thread(new threadstart());
th.start();

public void showwaritform(object obj)
{
  using(Waitform frm=new Waitform)
{
frm.topmoast=true;
frm.showdialog();
}
}

public class Waitform:Form
{
public Waitform()
{
  //加个Timer 定时几秒把这个窗口close就可以了。
}

Waitform_onload (object sender)
{
  
}
}


这种方法界面不会卡住。