Arc Engine二次开发——弹窗进行属性查询

在Arcmap中使用Sapefile格式的矢量数据时，经常会用到其属性查询的功能，弹出窗体然后用户鼠标点击或手动输入查询条件，进而查询到感兴趣的要素。在AE二次开发中也经常需要这个功能，于是在此记录整个开发过程。

首先当然是需要构建一个Visual C# Windows窗体应用程序，然后添加axMapControl等控件，这些过程不再赘述。

然后新建一个名为FormQueryAttr.cs的窗体，用于属性查询时弹出，其界面设置为如下：

其中要素为：一个ComboBox（cboLayer）；两个ListBox（listBoxField和listBoxValue）；一个GroupBox；一个TextBox（textBoxSql）

21个Button，表达式所需的19个button的名称如下：

btnequal、btnunequal、btnis、btnlike、btnmore、btnless、btnmoe、btnloe、btnor、btnnull、btnnot、btnand、btnin、btnunderline、btnpercent、btncharacter、btnbetween、btnspace、btnempty

点击查看代码，添加以下变量并在构造函数中添加以下语句：

 1         //地图数据 
 2         private AxMapControl mMapControl;
 3         //选中的图层 
 4         private IFeatureLayer mFeatureLayer;
 5         //根据所选择的图层查询得到的特征类
 6         private IFeatureClass pFeatureClass = null;
 7 
 8         public FormQueryAttr(AxMapControl mapControl)
 9         {
10             InitializeComponent();
11             this.mMapControl = mapControl;
12         }

接着回到程序主界面，添加属性查询的Button按钮，在其点击响应函数中添加如下代码：

1         //属性查询
2         private void barButtonItem13_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
3         {
4             FormQueryAttr formqueryattr = new FormQueryAttr(this.axMapControl1);
5             formqueryattr.Show();
6         }

至此，程序运行且用户点击“属性查询”按钮时，会初始化FormQueryAttr.cs窗体，将整个axMapControl作为参数传入，并显示窗体。

然后再回到FormQueryAttr.cs窗体的代码中，做以下更改：

在其Load函数中为cboLayer添加所有图层名称，代码如下：

 1         private void FormQueryAttr_Load(object sender, EventArgs e)
 2         {
 3             //MapControl中没有图层时返回 
 4             if (this.mMapControl.LayerCount <= 0)
 5                 return;
 6             //获取MapControl中的全部图层名称，并加入ComboBox 
 7             ILayer pLayer;
 8             //图层名称 
 9             string strLayerName;
10             for (int i = 0; i < this.mMapControl.LayerCount; i++)
11             {
12                 pLayer = this.mMapControl.get_Layer(i);
13                 strLayerName = pLayer.Name;
14                 //图层名称加入cboLayer 
15                 this.cboLayer.Items.Add(strLayerName);
16             }
17             //默认显示第一个选项 
18             this.cboLayer.SelectedIndex = 0;
19         }

为cboLayer添加SelectedIndexChanged响应事件，其中代码如下：

 1         private void cboLayer_SelectedIndexChanged(object sender, EventArgs e)
 2         {
 3             this.listBoxField.Items.Clear();
 4             //获取cboLayer中选中的图层 
 5             mFeatureLayer = mMapControl.get_Layer(cboLayer.SelectedIndex) as IFeatureLayer;
 6             pFeatureClass = mFeatureLayer.FeatureClass;
 7             string strFldName;
 8             for (int i = 0; i < pFeatureClass.Fields.FieldCount; i++)
 9             {
10                 strFldName = pFeatureClass.Fields.get_Field(i).Name;
11                 this.listBoxField.Items.Add(strFldName);
12             }
13             this.listBoxField.SelectedIndex = 0;
14             this.label8.Text = mFeatureLayer.Name;
15         }

为listBoxField添加SelectedIndexChanged和DoubleClick响应事件，其中代码如下：

 1         private void listBoxField_SelectedIndexChanged(object sender, EventArgs e)
 2         {
 3             string sFieldName = listBoxField.Text;
 4             listBoxValue.Items.Clear();
 5             int iFieldIndex = 0;
 6             IField pField = null;
 7             IFeatureCursor pFeatCursor = pFeatureClass.Search(null, true);
 8             IFeature pFeat = pFeatCursor.NextFeature();
 9             iFieldIndex = pFeatureClass.FindField(sFieldName);
10             pField = pFeatureClass.Fields.get_Field(iFieldIndex);
11             while (pFeat != null)
12             {
13                 listBoxValue.Items.Add(pFeat.get_Value(iFieldIndex));
14                 pFeat = pFeatCursor.NextFeature();
15             }
16 
17         }
18         private void listBoxField_DoubleClick(object sender, EventArgs e)
19         {
20             textBoxSql.SelectedText = listBoxField.SelectedItem.ToString() + " ";
21         }

为listBoxValue添加DoubleClick响应事件，其中代码如下：

1         private void listBoxValue_DoubleClick(object sender, EventArgs e)
2         {
3             textBoxSql.SelectedText = listBoxValue.SelectedItem.ToString() + " ";
4         }

然后对“表达式”中的按钮添加对应的点击响应函数，具体代码如下：

 1         private void btnequal_Click(object sender, EventArgs e)
 2         {
 3             textBoxSql.SelectedText = "= ";
 4         }
 5 
 6         private void btnis_Click(object sender, EventArgs e)
 7         {
 8             textBoxSql.SelectedText = "is ";
 9         }
10 
11         private void btncharacter_Click(object sender, EventArgs e)
12         {
13             textBoxSql.SelectedText = "'' ";
14         }
15 
16         private void btnempty_Click(object sender, EventArgs e)
17         {
18             this.textBoxSql.Text = "";
19         }
20 
21         private void btnunequal_Click(object sender, EventArgs e)
22         {
23             textBoxSql.SelectedText = "!= ";
24         }
25 
26         private void btnlike_Click(object sender, EventArgs e)
27         {
28             textBoxSql.SelectedText = "like ";
29         }
30 
31         private void btnmore_Click(object sender, EventArgs e)
32         {
33             textBoxSql.SelectedText = "> ";
34         }
35 
36         private void btnmoe_Click(object sender, EventArgs e)
37         {
38             textBoxSql.SelectedText = ">= ";
39         }
40 
41         private void btnloe_Click(object sender, EventArgs e)
42         {
43             textBoxSql.SelectedText = "<= ";
44         }
45 
46         private void btnor_Click(object sender, EventArgs e)
47         {
48             textBoxSql.SelectedText = " or ";
49         }
50 
51         private void btnnull_Click(object sender, EventArgs e)
52         {
53             textBoxSql.SelectedText = "Null ";
54         }
55 
56         private void btnless_Click(object sender, EventArgs e)
57         {
58             textBoxSql.SelectedText = "< ";
59         }
60 
61         private void btnnot_Click(object sender, EventArgs e)
62         {
63             textBoxSql.SelectedText = " Not ";
64         }
65 
66         private void btnand_Click(object sender, EventArgs e)
67         {
68             textBoxSql.SelectedText = " And ";
69         }
70 
71         private void btnin_Click(object sender, EventArgs e)
72         {
73             textBoxSql.SelectedText = " In ";
74         }
75 
76         private void btnunderline_Click(object sender, EventArgs e)
77         {
78             textBoxSql.SelectedText = "_";
79         }
80 
81         private void btnpercent_Click(object sender, EventArgs e)
82         {
83             textBoxSql.SelectedText = "% ";
84         }
85 
86         private void btnbetween_Click(object sender, EventArgs e)
87         {
88             textBoxSql.SelectedText = " Between ";
89         }
90 
91         private void btnspace_Click(object sender, EventArgs e)
92         {
93             textBoxSql.SelectedText = " ";
94         }

View Code

最后对按钮“查找”和“取消”添加点击响应函数，代码如下：

 1         private void button1_Click(object sender, EventArgs e)
 2         {
 3             try
 4             {
 5                 mMapControl.Map.ClearSelection(); //清除上次查询结果
 6                 IActiveView pActiveView = mMapControl.Map as IActiveView;
 7                 //pQueryFilter的实例化 
 8                 IQueryFilter pQueryFilter = new QueryFilterClass();
 9                 //设置查询过滤条件 
10                 pQueryFilter.WhereClause = textBoxSql.Text;
11                 //search的参数第一个为过滤条件，第二个为是否重复执行
12                 IFeatureCursor pFeatureCursor = mFeatureLayer.Search(pQueryFilter, false);
13                 //获取查询到的要素 
14                 IFeature pFeature = pFeatureCursor.NextFeature();
15                 //判断是否获取到要素 
16                 while (pFeature != null)
17                 {
18                     mMapControl.Map.SelectFeature(mFeatureLayer, pFeature); //选择要素 
19                     pFeature = pFeatureCursor.NextFeature();
20                 }
21                 pActiveView.PartialRefresh(esriViewDrawPhase.esriViewGeoSelection, null, null);
22                 pActiveView.Refresh();//刷新图层
23             }
24             catch (Exception ex)
25             {
26                 MessageBox.Show(ex.Message);
27             }
28 
29         }
30 
31         private void button2_Click(object sender, EventArgs e)
32         {
33             this.Hide();
34         }

到此为止，所有属性查询的工作已经完成，使用效果如下图所示：

如果需要清除所选要素，则添加按钮，并在其点击响应函数中添加如下代码即可：

1         //清空查询
2         private void barButtonItem14_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
3         {
4             axMapControl1.Map.ClearSelection();
5             axMapControl1.Refresh();
6         }