namespace Test
{
    public partial class ShowValue : Form
    {
        public int nID = 0;
        public ShowValue()
        {
            InitializeComponent();
            MessageBox.Show(nID.ToString());
        }
    }
}

------解决方案--------------------
GisChartWindow子窗口中设置属性,例如:
C# code

namespace Test
{
    public partial class GisChartWindow : Form
    {
        public int nID = 0;
        public ShowValue()
        {
            InitializeComponent();
            MessageBox.Show(nID.ToString());
        }
    }
}

------解决方案--------------------
2次都搞错了，把ShowValue改成GisChartWindow就行

------解决方案--------------------
private void SiPingRuiAn_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
 {
 GisChartWindow gischartwindow = new GisChartWindow("A楼", "B001");
 gischartwindow.Show();
 }

public GisChartWindow(string title, string tag)
 {
 InitializeComponent();
 string str1 = title;
 string str2 = tag;
 }

------解决方案--------------------
构造函数里加。

------解决方案--------------------
在子窗口Load方法里进行赋值不就好了
1、赋值
C# code

private void SiPingRuiAn_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    GisChartWindow gischartwindow = new GisChartWindow();
    gischartwindow.strParam1 = "A楼";
    gischartwindow.strParam2 = "B001";
    gischartwindow.Show();
}