[原创]如何计算所有记录数所占内存大小

楼主^#

更多发布于：2009-08-04 09:57

如何计算featureclass中的所有记录数所占内存大小 
...... 
for (int j = 0; j < iCount; j++) 
 { 
 
 string strLayerName = ptrAOStringArray.get_Element(j); 
 
 IFeatureClass ptrFeatureClass = ptrFWorkspace.OpenFeatureClass(strLayerName); 
 
 IFeatureCursor ptrCursor = ptrFeatureClass.Search(null, false); 
 IFeature ptrFeature = ptrCursor.NextFeature(); 
 
 IFields ptrFields = ptrFeatureClass.Fields; 
 int FieldNums = ptrFields.FieldCount; 
 int iAttributeSize = 0; 
 for (int k = 0; k < FieldNums; k++) 
 { 
 IField ptrField = ptrFields.get_Field(k); 
 esriFieldType fieldType = ptrField.Type; 
 switch (fieldType) 
 { 
 case esriFieldType.esriFieldTypeDate: 
 { 
 string strValue = ptrFeature.get_Value(k).ToString(); 
 
 iAttributeSize += strValue.Length *
System.Runtime.InteropServices.Marshal.SizeOf(typeof(char)); 
 } 
 break; 
 case esriFieldType.esriFieldTypeDouble: 
 { 
 iAttributeSize += System.Runtime.InteropServices.Marshal.SizeOf(typeof(double)); 
 } 
 break; 
 case esriFieldType.esriFieldTypeInteger: 
 { 
 iAttributeSize += System.Runtime.InteropServices.Marshal.SizeOf(typeof(long)); 
 } 
 break; 
 case esriFieldType.esriFieldTypeOID: 
 { 
 iAttributeSize += System.Runtime.InteropServices.Marshal.SizeOf(typeof(long)); 
 } 
 break; 
 case esriFieldType.esriFieldTypeSingle: 
 { 
 iAttributeSize += System.Runtime.InteropServices.Marshal.SizeOf(typeof(float)); 
 } 
 break; 
 case esriFieldType.esriFieldTypeString: 
 { 
 string strValue = ptrFeature.get_Value(k).ToString(); 
 
 iAttributeSize += strValue.Length *
System.Runtime.InteropServices.Marshal.SizeOf(typeof(char)); 
 } 
 break; 
 case esriFieldType.esriFieldTypeSmallInteger: 
 { 
 iAttributeSize += System.Runtime.InteropServices.Marshal.SizeOf(typeof(short)); 
 } 
 break; 
 default: 
 break; 
 
 } 
 } 
 
 esriGeometryType geoType = ptrFeature.Shape.GeometryType; 
 int iAttributeSize2 = iAttributeSize; 
 int FileIndex = 1; 
 bool bSplit = false; 
 int Features = 1; 
 int nPos = ptrFeature.OID - 1; 
 while (ptrFeature != null) 
 { 
 switch (geoType) 
 { 
 case esriGeometryType.esriGeometryMultipoint: 
 { 
 IMultipoint mpoint = ptrFeature.Shape as IMultipoint; 
 IPointCollection pts = mpoint as IPointCollection; 
 
 iAttributeSize2 += pts.PointCount *
System.Runtime.InteropServices.Marshal.SizeOf(typeof(double)) * 4; 
 } 
 break; 
 case esriGeometryType.esriGeometryPoint: 
 { 
 IPoint point = ptrFeature.Shape as IPoint; 
 iAttributeSize2 += System.Runtime.InteropServices.Marshal.SizeOf(typeof(double)) * 4; 
 } 
 break; 
 case esriGeometryType.esriGeometryPolyline: 
 { 
 IPolyline line = ptrFeature.Shape as IPolyline; 
 IPointCollection pts = line as IPointCollection; 
 iAttributeSize2 += pts.PointCount *
System.Runtime.InteropServices.Marshal.SizeOf(typeof(double)) * 4; 
 } 
 break; 
 case esriGeometryType.esriGeometryPolygon: 
 { 
 IPolygon poly = ptrFeature.Shape as IPolygon; 
 IPointCollection pts = poly as IPointCollection; 
 iAttributeSize2 += pts.PointCount *
System.Runtime.InteropServices.Marshal.SizeOf(typeof(double)) * 4; 
 } 
 break; 
 default: 
 break; 
 
 } 
 System.Runtime.InteropServices.Marshal.ReleaseComObject(ptrFeature); 
 
 Features++; 
 ptrFeature = ptrCursor.NextFeature(); 
} 
我目前是这样做的，但一个记录有几百万条时，效率非常低，不知道有什么好办法没有，请知道的朋友帮忙指点指点

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xiaoshengzi 路人甲注册日期2008-09-16 发帖数4 QQ 铜币108枚威望0点贡献值0点银元0个加关注写私信	1楼^# 发布于：2009-08-04 14:35 我想知道大家有没有更高效的算法
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cl991036

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注册日期2003-07-25
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2楼^#

发布于：2009-08-04 14:33

循环中可以重复使用变量尽量写到循环外面去

没钱又丑，农村户口。头可断，发型一定不能乱。邮箱:gisempire@qq.com

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xiaoshengzi 路人甲注册日期2008-09-16 发帖数4 QQ 铜币108枚威望0点贡献值0点银元0个加关注写私信	3楼^# 发布于：2009-08-04 13:50 ArcObjects of technical merit is very low! sigh<br>
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[原创]如何计算所有记录数所占内存大小

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