在AE中创建内存图层(转载)

使用IWorkspaceFactory,IWorkspaceName,IName,IWorkspace等接口以及InMemoryWorkspaceFactoryClass对象创建在程序运行时的内存中的矢量要素层

 

直接上代码：

///<summary>///
在程序运行时的内存中创建矢量要素层，并加到地图控件最顶端
///</summary> ///
<param name="pMapCtrl">地图控件</param>
///<returns>IFeatureLayer 新加的要素层</returns>

private IFeatureLayer AddFeatureLayerByMemoryWS(AxMapControl pMapCtrl, ISpatialReference pSReference)
{
try
{
if (pMapCtrl == null)
return null;
//创建新的内存工作空间
IWorkspaceFactory pWSF = new InMemoryWorkspaceFactoryClass();
IWorkspaceName pWSName = pWSF.Create("","Temp",null,0);
IName pName = (IName)pWSName;
IWorkspace pMemoryWS = (IWorkspace)pName.Open();

IField oField = new FieldClass();
IFields oFields = new FieldsClass();
IFieldsEdit oFieldsEdit = null;
IFieldEdit oFieldEdit = null;
IFeatureClass oFeatureClass = null;
IFeatureLayer oFeatureLayer = null;
try
{
oFieldsEdit = oFields as IFieldsEdit;
oFieldEdit = oField as IFieldEdit;
oFieldEdit.Name_2 = "OBJECTID";
oFieldEdit.Type_2 = esriFieldType.esriFieldTypeOID;
oFieldEdit.IsNullable_2 = false;
oFieldEdit.Required_2 = false;
oFieldsEdit.AddField(oField);

oField = new FieldClass();
oFieldEdit = oField as IFieldEdit;
IGeometryDef pGeoDef = new GeometryDefClass();
IGeometryDefEdit pGeoDefEdit = (IGeometryDefEdit)pGeoDef;
pGeoDefEdit.AvgNumPoints_2 = 5;
pGeoDefEdit.GeometryType_2 = esriGeometryType.esriGeometryPolygon;
pGeoDefEdit.GridCount_2 = 1;
pGeoDefEdit.HasM_2 = false;
pGeoDefEdit.HasZ_2 = false;
pGeoDefEdit.SpatialReference_2 = pSReference;
oFieldEdit.Name_2 = "SHAPE";
oFieldEdit.Type_2 = esriFieldType.esriFieldTypeGeometry;
oFieldEdit.GeometryDef_2 = pGeoDef;
oFieldEdit.IsNullable_2 = true;
oFieldEdit.Required_2 = true;
oFieldsEdit.AddField(oField);

oField = new FieldClass();
oFieldEdit = oField as IFieldEdit;
oFieldEdit.Name_2 = "Code";
oFieldEdit.Type_2 = esriFieldType.esriFieldTypeSmallInteger;
oFieldEdit.IsNullable_2 = true;
oFieldsEdit.AddField(oField);

//创建要素类
oFeatureClass = (pMemoryWS as IFeatureWorkspace).CreateFeatureClass("Temp", oFields, null, null, esriFeatureType.esriFTSimple, "SHAPE", "");
oFeatureLayer = new FeatureLayerClass();
oFeatureLayer.Name = "TransTemp";
oFeatureLayer.FeatureClass = oFeatureClass;

//创建唯一值符号化对象
IUniqueValueRenderer pURender = new UniqueValueRendererClass();
pURender.FieldCount = 1;
pURender.set_Field(0, "Code");
pURender.UseDefaultSymbol = false;
ISimpleFillSymbol pFillSym = new SimpleFillSymbolClass();
pFillSym.Style = esriSimpleFillStyle.esriSFSSolid;
//半透明颜色
IRgbColor pColor = new RgbColorClass();
pColor.Red = 255;
pColor.Green = 255;
pFillSym.Color = pColor;
pURender.AddValue("1", "", pFillSym as ISymbol);
pFillSym = new SimpleFillSymbolClass();
pFillSym.Style = esriSimpleFillStyle.esriSFSSolid;
//唯一值符号化内存图层
(oFeatureLayer as IGeoFeatureLayer).Renderer = pURender as IFeatureRenderer;
ILayerEffects pLyrEffect = oFeatureLayer as ILayerEffects;
//透明度
pLyrEffect.Transparency = 80;
}
catch (Exception Err)
{
MessageBox.Show(Err.Message);
}

finally
{
try{
System.Runtime.InteropServices.Marshal.ReleaseComObject(oField);
System.Runtime.InteropServices.Marshal.ReleaseComObject(oFields);
System.Runtime.InteropServices.Marshal.ReleaseComObject(oFieldsEdit);
System.Runtime.InteropServices.Marshal.ReleaseComObject(oFieldEdit);
System.Runtime.InteropServices.Marshal.ReleaseComObject(pName);
System.Runtime.InteropServices.Marshal.ReleaseComObject(pWSF);
System.Runtime.InteropServices.Marshal.ReleaseComObject(pWSName);
System.Runtime.InteropServices.Marshal.ReleaseComObject(pMemoryWS);
System.Runtime.InteropServices.Marshal.ReleaseComObject(oFeatureClass);
}
catch
{

}
GC.Collect();
}
return oFeatureLayer;
}
catch (Exception Err)
{
MessageBox.Show(Err.Message, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
return null;
}


}