ArcGIS Engine效率探究之（一）属性的读取

原文链接：/article/10309803.html

对属性表的统计函数时，发现执行速度奇慢无比，百思不得其解，其实算法并不复杂，后来逐句排查终于发现竟是 ArcGIS
Engine 的函数读取属性值的问题。

在获取属性表的值时有多种方法：

方法一：

ITable pTable = pFeatureClass as ITable;

pValue = pTable.GetRow(i).get_Value(3);

方法二：

IFeatureCursor pFCursor = pFeatureClass.Search(new QueryFilterClass(), false);

IFeature pFeature = pFCursor.NextFeature();

if (pFeature == null) return null;

pValue = pFeature.get_Value(pIndex);

pFeature = pFCursor.NextFeature();

方法二明显要快于方法一

实例测试：

//目标是想将原数据库中的点信息(x,y经纬度坐标,度格式),添加到FeatureClass中，数据库中大概有10000条数据,全部添加到FeatureClass中大概需

//要半小时以上

DataSet ds = loadExcel("d://aaa.xls");
IFeature feature = featureClass.CreateFeature();
IFields fields = featureClass.Fields;
for(int i=0;i<ds.Tables[0].Rows.Count;i++)
{
DataRow row = ds.Tables[0].Rows[i];
string xl = Convert.ToString(row[0]);
string x = Convert.ToDouble(row[1]);
string y = Convert.ToDouble(row[2]);
//....其它数据库中字段
//创建点对象
IPoint point = new PointClass();
point.X = x;
point.Y = y;
//设置Fields域
feature.set_Value(fields.FindField("线路"),xl);
feature.set_Value(fields.FindField("经度"),x);
feature.set_Value(fields.FindField("纬度"),y);
//保存点对象
feature.Shape = point;
feature.Store();
}
//改进后：
DataSet ds = loadExcel("d://aaa.xls")
IFeatureBuffer featureBuffer;//
IFeatureCursor cur = featureClass.Insert(true);
IPoint point;
IFields fields = featureClass.Fields;
for(int i=0;i<ds.Tables[0].Rows.Count;i++)

{
DataRow row = ds.Tables[0].Rows[i];
string xl = Convert.ToString(row[0]);
string x = Convert.ToDouble(row[1]);
string y = Convert.ToDouble(row[2]);
//....其它数据库中字段
//创建点对
point = new PointClass();
point.X = x;
point.Y = y;
featureBuffer = featureClass.CreateFeatureBuffer();
//设置Fields域
featureBuffer.set_Value(fields.FindField("线路"),xl);
featureBuffer.set_Value(fields.FindField("经度"),x);
featureBuffer.set_Value(fields.FindField("纬度"),y);
//保存点对象
featureBuffer.Shape = point;
cur.InsertFeature(featureBuffer);
}

//可以看出改进后使用了eatureClass.CreateFeatureBuffer方法，使效率大大提高。