private void btOK_Click(object sender, EventArgs e)
{
if (cboBoxPointLayer.SelectedItem == null)
{
MessageBox.Show("请加载点图层！");
return;
}
if (txtLineFilePath.Text == "")
{
MessageBox.Show("请输入要输出线图层的路径及名称！");
return;
}
try
{
//从点图层中读取所有点
string pPointFileName = cboBoxPointLayer.SelectedItem.ToString();
ILayer pLayer = null;
for (int i = 0; i < pMapcontrol.LayerCount; i++)
{
if (pPointFileName == pMapcontrol.get_Layer(i).Name)
{
pLayer = pMapcontrol.get_Layer(i);
}
}
psf = ((IGeoDataset)pLayer).SpatialReference;
IFeatureLayer pFeatureLayerPoint = pLayer as IFeatureLayer;
IPointCollection PointCollection = ReadPoint(pFeatureLayerPoint);
//判断需要生成的线文件是否存在，若不存在则创建文件，若存在则将新添加的线写入文件
if (File.Exists(txtLineFilePath.Text))
{
//若已经存在则读取结尾点并加入到PointCollection
string pLineFile = txtLineFilePath.Text;
string pFilePath = System.IO.Path.GetDirectoryName(pLineFile);
string pFileName = System.IO.Path.GetFileName(pLineFile);
//打开工作空间
IWorkspaceFactory pWSF = new ShapefileWorkspaceFactoryClass();
IFeatureWorkspace pWS = (IFeatureWorkspace)pWSF.OpenFromFile(pFilePath, 0);
IFeatureLayer pFeatureLayer = new FeatureLayerClass();
pFeatureLayer.FeatureClass = pWS.OpenFeatureClass(pFileName);
IField pField = null;
if (pFeatureLayer.FeatureClass.Fields.FindField("FID") != -1)
{
pField = pFeatureLayer.FeatureClass.Fields.get_Field(pFeatureLayer.FeatureClass.Fields.FindField("FID"));
}
else if (pFeatureLayer.FeatureClass.Fields.FindField("OBJECTID") != -1)
{
pField = pFeatureLayer.FeatureClass.Fields.get_Field(pFeatureLayer.FeatureClass.Fields.FindField("OBJECTID"));
}
//第一个属性字段名称
string FirstFieldName = pField.AliasName;
IQueryFilter pQueryFilter = new QueryFilterClass();
pQueryFilter.WhereClause = FirstFieldName + ">=0";
int number = pFeatureLayer.FeatureClass.FeatureCount(pQueryFilter);
IFeature pFeature;
if (FirstFieldName == "FID")
{
pFeature = pFeatureLayer.FeatureClass.GetFeature(number - 1);
}
else
{
pFeature = pFeatureLayer.FeatureClass.GetFeature(number);
}
IGeometry pGeometry = pFeature.Shape as IGeometry;
IPolyline pPolyline = pGeometry as IPolyline;
IPointCollection pPointCollection = new MultipointClass();
pPointCollection.AddPoint(pPolyline.ToPoint);
PointCollection.InsertPointCollection(0, pPointCollection);
}
else
{
//不存在则创建新的线图层
CreateNewLineLayer();
}
//将所有的点连接成线
IPolyline Polyline = CreatePolyline(PointCollection);
//将连接成的线添加到线图层中
AddFeature(Polyline as IGeometry);
MessageBox.Show("成功生成中线");
this.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}