Arc Engine二次開發——彈窗進行屬性查詢

在Arcmap中使用Sapefile格式的矢量數據時，經常會用到其屬性查詢的功能，彈出窗體然后用戶鼠標點擊或手動輸入查詢條件，進而查詢到感興趣的要素。在AE二次開發中也經常需要這個功能，於是在此記錄整個開發過程。

首先當然是需要構建一個Visual C# Windows窗體應用程序，然后添加axMapControl等控件，這些過程不再贅述。

然后新建一個名為FormQueryAttr.cs的窗體，用於屬性查詢時彈出，其界面設置為如下：

其中要素為：一個ComboBox（cboLayer）；兩個ListBox（listBoxField和listBoxValue）；一個GroupBox；一個TextBox（textBoxSql）

21個Button，表達式所需的19個button的名稱如下：

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

 

點擊查看代碼，添加以下變量並在構造函數中添加以下語句：

        //地圖數據 
        private AxMapControl mMapControl;
        //選中的圖層 
        private IFeatureLayer mFeatureLayer;
        //根據所選擇的圖層查詢得到的特征類
        private IFeatureClass pFeatureClass = null;

        public FormQueryAttr(AxMapControl mapControl)
        {
            InitializeComponent();
            this.mMapControl = mapControl;
        }

接着回到程序主界面，添加屬性查詢的Button按鈕，在其點擊響應函數中添加如下代碼：

        //屬性查詢
        private void barButtonItem13_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
        {
            FormQueryAttr formqueryattr = new FormQueryAttr(this.axMapControl1);
            formqueryattr.Show();
        }

至此，程序運行且用戶點擊“屬性查詢”按鈕時，會初始化FormQueryAttr.cs窗體，將整個axMapControl作為參數傳入，並顯示窗體。

然后再回到FormQueryAttr.cs窗體的代碼中，做以下更改：

在其Load函數中為cboLayer添加所有圖層名稱，代碼如下：

        private void FormQueryAttr_Load(object sender, EventArgs e)
        {
            //MapControl中沒有圖層時返回 
            if (this.mMapControl.LayerCount <= 0)
                return;
            //獲取MapControl中的全部圖層名稱，並加入ComboBox 
            ILayer pLayer;
            //圖層名稱 
            string strLayerName;
            for (int i = 0; i < this.mMapControl.LayerCount; i++)
            {
                pLayer = this.mMapControl.get_Layer(i);
                strLayerName = pLayer.Name;
                //圖層名稱加入cboLayer 
                this.cboLayer.Items.Add(strLayerName);
            }
            //默認顯示第一個選項 
            this.cboLayer.SelectedIndex = 0;
        }

為cboLayer添加SelectedIndexChanged響應事件，其中代碼如下：

        private void cboLayer_SelectedIndexChanged(object sender, EventArgs e)
        {
            this.listBoxField.Items.Clear();
            //獲取cboLayer中選中的圖層 
            mFeatureLayer = mMapControl.get_Layer(cboLayer.SelectedIndex) as IFeatureLayer;
            pFeatureClass = mFeatureLayer.FeatureClass;
            string strFldName;
            for (int i = 0; i < pFeatureClass.Fields.FieldCount; i++)
            {
                strFldName = pFeatureClass.Fields.get_Field(i).Name;
                this.listBoxField.Items.Add(strFldName);
            }
            this.listBoxField.SelectedIndex = 0;
            this.label8.Text = mFeatureLayer.Name;
        }

為listBoxField添加SelectedIndexChanged和DoubleClick響應事件，其中代碼如下：

        private void listBoxField_SelectedIndexChanged(object sender, EventArgs e)
        {
            string sFieldName = listBoxField.Text;
            listBoxValue.Items.Clear();
            int iFieldIndex = 0;
            IField pField = null;
            IFeatureCursor pFeatCursor = pFeatureClass.Search(null, true);
            IFeature pFeat = pFeatCursor.NextFeature();
            iFieldIndex = pFeatureClass.FindField(sFieldName);
            pField = pFeatureClass.Fields.get_Field(iFieldIndex);
            while (pFeat != null)
            {
                listBoxValue.Items.Add(pFeat.get_Value(iFieldIndex));
                pFeat = pFeatCursor.NextFeature();
            }

        }
        private void listBoxField_DoubleClick(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = listBoxField.SelectedItem.ToString() + " ";
        }

為listBoxValue添加DoubleClick響應事件，其中代碼如下：

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

然后對“表達式”中的按鈕添加對應的點擊響應函數，具體代碼如下：

        private void btnequal_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "= ";
        }

        private void btnis_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "is ";
        }

        private void btncharacter_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "'' ";
        }

        private void btnempty_Click(object sender, EventArgs e)
        {
            this.textBoxSql.Text = "";
        }

        private void btnunequal_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "!= ";
        }

        private void btnlike_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "like ";
        }

        private void btnmore_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "> ";
        }

        private void btnmoe_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = ">= ";
        }

        private void btnloe_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "<= ";
        }

        private void btnor_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = " or ";
        }

        private void btnnull_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "Null ";
        }

        private void btnless_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "< ";
        }

        private void btnnot_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = " Not ";
        }

        private void btnand_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = " And ";
        }

        private void btnin_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = " In ";
        }

        private void btnunderline_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "_";
        }

        private void btnpercent_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = "% ";
        }

        private void btnbetween_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = " Between ";
        }

        private void btnspace_Click(object sender, EventArgs e)
        {
            textBoxSql.SelectedText = " ";
        }

最后對按鈕“查找”和“取消”添加點擊響應函數，代碼如下：

        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                mMapControl.Map.ClearSelection(); //清除上次查詢結果
                IActiveView pActiveView = mMapControl.Map as IActiveView;
                //pQueryFilter的實例化 
                IQueryFilter pQueryFilter = new QueryFilterClass();
                //設置查詢過濾條件 
                pQueryFilter.WhereClause = textBoxSql.Text;
                //search的參數第一個為過濾條件，第二個為是否重復執行
                IFeatureCursor pFeatureCursor = mFeatureLayer.Search(pQueryFilter, false);
                //獲取查詢到的要素 
                IFeature pFeature = pFeatureCursor.NextFeature();
                //判斷是否獲取到要素 
                while (pFeature != null)
                {
                    mMapControl.Map.SelectFeature(mFeatureLayer, pFeature); //選擇要素 
                    pFeature = pFeatureCursor.NextFeature();
                }
                pActiveView.PartialRefresh(esriViewDrawPhase.esriViewGeoSelection, null, null);
                pActiveView.Refresh();//刷新圖層
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }

        }

        private void button2_Click(object sender, EventArgs e)
        {
            this.Hide();
        }

到此為止，所有屬性查詢的工作已經完成，使用效果如下圖所示：

如果需要清除所選要素，則添加按鈕，並在其點擊響應函數中添加如下代碼即可：

        //清空查詢
        private void barButtonItem14_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
        {
            axMapControl1.Map.ClearSelection();
            axMapControl1.Refresh();
        }