一、AE缓冲区接口和类

还是老生常谈，先来了解实现缓冲区功能都需要那些接口和类：
GP工具：也就是Geoprocessor类，这其中主要是封装了输入路径、输出路径还有就是可以调用各种工具的函数方法。它给我的感觉类似于原来我是一亩地一亩地的打农药，突然有一天来了一架飞机直接在天上散农药，一下子活就干完了。这GP工具就是那飞机，它大大的提高了效率。
Buffer类：这里注意了这是AnalysisTools下的Buffer类，我记得有两个buffer类，下图是Buffer类中的参数设置表。
在这里插入图片描述图有点不清晰，我就只能截一点相对重要的信息。

二、功能的实现

2.1功能实现代码

private IActiveView pActiveView;
   private AxMapControl mapControl;
   //通过构造函数获取MapControl控件
   public BufferAnalysis(AxMapControl mainmapControl)
       : this()
   { 
       mapControl = mainmapControl;
       pActiveView = mainmapControl.ActiveView;
   }
   //输出路径
   private void button1_OutputPath_Click(object sender, EventArgs e)
   { 
       SaveFileDialog saveDlg = new SaveFileDialog();
       saveDlg.Filter = "Shapefile(*.shp)|*.shp";
       if (saveDlg.ShowDialog() != DialogResult.OK) return;
       textBox2_OutputPath.Text = saveDlg.FileName;
   }
   //生成窗体函数
   private void BufferAnalysis_Load(object sender, EventArgs e)
   { 
       if (mapControl == null || pActiveView.FocusMap.LayerCount == 0)
       { 
           return;
       }
       IEnumLayer layers = pActiveView.FocusMap.get_Layers();
       layers.Reset();
       ILayer layer = layers.Next();
       while (layer != null)
       { 
           comboBox1_ChooseLayer.Items.Add(layer.Name);
           layer = layers.Next();
       }
   }
   //确认分析
   private void button2_OK_Click(object sender, EventArgs e)
   { 
       double bufferDistance = Convert.ToDouble(textBox1_BufferDistance.Text.Trim());
       if (bufferDistance == 0.0)
       { 
           MessageBox.Show("缓冲区距离有误！");
           return;
       }
       if (comboBox1_ChooseLayer.Text == string.Empty)
       { 
           MessageBox.Show("输入图层不能为空！");
           return;
       }
       if (textBox2_OutputPath.Text == string.Empty)
       { 
           MessageBox.Show("输出路径不能为空！");
           return;
       }
       int index = comboBox1_ChooseLayer.SelectedIndex;
       string name = getLayerPath(pActiveView.FocusMap.get_Layer(index));
       string outPath = textBox2_OutputPath.Text.Trim();
       Geoprocessor pGp = new Geoprocessor();
       pGp.OverwriteOutput = true; //允许运算结果覆盖现有文件，可无
       ESRI.ArcGIS.AnalysisTools.Buffer pBuffer = new ESRI.ArcGIS.AnalysisTools.Buffer();
       //获取缓冲区分析图层
       ILayer pLayer = pActiveView.FocusMap.get_Layer(index);
       IFeatureLayer featLayer = pLayer as IFeatureLayer;
       //IFeatureCursor cursor = featLayer.Search(null, false);
       //IFeature feaClass = cursor.NextFeature();
       pBuffer.in_features = featLayer;
       pBuffer.out_feature_class = outPath; //输出路径
       pBuffer.buffer_distance_or_field = bufferDistance; //缓冲区参数
       pBuffer.dissolve_option = "NONE"; //融合缓冲区重叠交叉部分，如果不融合填"ALL"
       pGp.Execute(pBuffer, null); //执行
       string pFolder = System.IO.Path.GetDirectoryName(outPath); //得到字符串中文件夹位置
       string pFileName = System.IO.Path.GetFileName(outPath); //得到字符串中文件名字
       mapControl.AddShapeFile(pFolder, pFileName); //往地图控件里添加文件
       mapControl.ActiveView.Refresh(); //激活窗口刷新
       this.Close();
   }
   //获取图层源路径
   private string getLayerPath(ILayer pLayer)
   { 
       IDatasetName pDatasetName = (pLayer as IDataLayer2).DataSourceName as IDatasetName;
       IWorkspaceName pWorkspaceName = pDatasetName.WorkspaceName;
       return pWorkspaceName.PathName +"\\" +pLayer.Name+".shp";
   }