编译到这句时候VideoControlProperty pVideoControlProperty = (VideoControlProperty)((Control)sender).Tag;
系统提示是 “未将对象引用设置到对象的实例”
本人新人 各位大虾指点，帮助！ 谢谢！

顶顶，大家来帮忙啊！！

麻烦楼主多帖点代码出来吧

这类型转换的太强了

private void PictureBox_MouseDown(object sender, MouseEventArgs e)
{
VideoControlProperty pVideoControlProperty = (VideoControlProperty)((Control)sender).Tag;
string pUniComNo = this.m_UniCamNoSelected = pVideoControlProperty.UniCamNo;
this.m_TextBoxCamNo.Text = pUniComNo;
string pCamName = this.GetCamNameByCamNo(pUniComNo);//this.m_CamNoAndName[pUniComNo].ToString();
this.m_BarStaticItemCam.Caption = "当前选中的摄象机为：" + pCamName;
this.m_ButtonRecordStart.Enabled = true;
this.m_ButtonSnap.Enabled = true;
this.button19.Enabled = true;
this.button20.Enabled = true;
this.button21.Enabled = true;
this.button22.Enabled = true;
this.button23.Enabled = true;

if (this.m_CurrentVideoCount == 20)
{
for (int i = 0; i < this.m_PictureBox20.Length; i++)
{
。。。 }
}
if (this.m_CurrentVideoCount == 16)
{
for (int i = 0; i < this.m_PictureBox16.Length; i++)
{
。。。
}
}
else if (this.m_CurrentVideoCount == 4)
{
for (int i = 0; i < this.m_PictureBox4.Length; i++)
{
if (this.m_PictureBox4[i].Equals(sender))
{
this.m_TextBoxWindowNo.Text = Convert.ToString(i+1);
break;
}
}
}

if (e.Button == MouseButtons.Right && e.Clicks == 1)
{
。。。
}
else if(e.Button ==MouseButtons.Middle)
{
this.ControlCamera(LenType.LensTele);
}
else if (e.Button == MouseButtons.Left && e.Clicks == 2)
{
。。。
}

[此贴子已经被作者于2007-9-11 17:05:26编辑过]

public struct VideoControlProperty
{
public string UniCamNo;
public string IpAddress;
public int RemoteChannel;
}

顶顶 大家看看

sender是一个你点击的控件，你却让它强制转化成一个struct，不知道可否啊

這麼初始化結構體肯定有問題的

VideoControlProperty ddd= new VideoControlProperty();
ddd.UniCamNo= (string)((Control)sender).Tag;

[此贴子已经被作者于2007-9-11 17:10:51编辑过]