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arcengine,深入理解游标Cursors，实现数据的快速查找，插入，删除，更新

2017-11-21 1379

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简介：

风过无痕 原文 arcengine,深入理解游标Cursors，实现数据的快速查找，插入，删除，更新

深入理解游标Cursors，实现数据的快速查找，插入，删除，更新

1、查找数据Search Cursors

//by yl landgis@126.com yanleigis@21cn.com 2008.7.7

IEnvelope envelope = new EnvelopeClass();
envelope.PutCoords(508786, 681196, 513033, 684341);
ISpatialFilter spatialFilter = new SpatialFilterClass();
spatialFilter.Geometry = envelope;
String shpFld = featureClass.ShapeFieldName;
spatialFilter.GeometryField = shpFld;
spatialFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelIntersects;
IQueryFilter queryFilter = new QueryFilterClass();
queryFilter = (IQueryFilter)spatialFilter;

IFeatureCursor searchCursor = featureClass.Search(queryFilter, true);//只查询，true快一些
IFeature feature = searchCursor.NextFeature();
int n = 0;
while (feature != null){
    n++;
    feature = baseCursor.NextFeature();
}

2、插入数据Insert Cursors—目前数据插入最快的方法

//by yl landgis@126.com yanleigis@21cn.com 2008.7.7

IFeatureBuffer featureBuffer = featureClass.CreateFeatureBuffer();
IFeatureCursor featureCursor = featureClass.Insert(true);
object featureOID;         
featureBuffer.set_Value(featureBuffer.Fields.FindField("InstBy"), "B Pierce");

for (int ic = 0; ic < 99; ic++) {      
   featureBuffer.Shape = geometry
   featureOID = featureCursor.InsertFeature(featureBuffer);
}

featureBuffer.set_Value(featureBuffer.Fields.FindField("InstBy"), "K Johnston");

for (int ic = 0; ic < 99; ic++)
{
     featureBuffer.Shape = geometry
     featureOID = featureCursor.InsertFeature(featureBuffer);
}

featureCursor.Flush();

3、数据删除 delete

//by yl landgis@126.com yanleigis@21cn.com 2008.7.7

IFeatureClass featureClass = featureWorkspace.OpenFeatureClass("Parcels");
 
IQueryFilter queryFilter = new QueryFilterClass();
queryFilter.WhereClause = "ZONING_S = 'R'";
IFeatureCursor updateCursor = featureClass.Update(queryFilter, false);

IFeature feature = updateCursor.NextFeature();
 
int m = 0;
while (feature != null)
{
    m++;
    updateCursor.DeleteFeature(feature);
    feature = updateCursor.NextFeature();
}

4、数据更新 update

 
           //by yl landgis@126.com yanleigis@21cn.com 2008.7.7
          
           IFeatureClass featureClass = featureWorkspace.OpenFeatureClass(
           "Parcels"
           ); 
          
           // restrict the number of features to be updated.
          
           IQueryFilter queryFilter = 
           new 
           QueryFilterClass(); 
          
           queryFilter.WhereClause = 
           "ZONING_S = 'U'"
           ; 
          
           // use IFeatureClass::Update to populate IFeatureCursor
          
           IFeatureCursor updateCursor = featureClass.Update(queryFilter, 
           false
           ); 
          
           int 
           fieldindex = featureClass.FindField(
           "ZONING_S"
           ); 
          
           IFeature feature = updateCursor.NextFeature();
          
           int 
           m = 0; 
          
           while 
           (feature != 
           null
           ) 
          
           {
          
           m++; 
          
           feature.set_Value(fieldindex, 
           "X"
           ); 
          
           updateCursor.UpdateFeature(feature); 
          
           feature = updateCursor.NextFeature(); 
          
           }

没有整理与归纳的知识，一文不值！高度概括与梳理的知识，才是自己真正的知识与技能。永远不要让自己的自由、好奇、充满创造力的想法被现实的框架所束缚，让创造力自由成长吧！多花时间，关心他（她）人，正如别人所关心你的。理想的腾飞与实现，没有别人的支持与帮助，是万万不能的。

本文转自wenglabs博客园博客，原文链接：http://www.cnblogs.com/arxive/p/6114330.html ，如需转载请自行联系原作者

arcengine,深入理解游标Cursors，实现数据的快速查找，插入，删除，更新

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