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C#读取shapefile文件

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;


using System.Data.Odbc; //add by hand,which is needed when load the layer attribute information
using System.Data.OleDb;
using System.Collections;
using System.Data;
using System.Xml;


namespace CGCL.CGFiles
{
public class CGShapeFileParser
{
public class ESRI_ShxHeader
{
int FileCode; //9994
int[] Unused2 = new int[5];
int FileLength;
int Version; //1000
int ShapeType; // 0- Null shape
// 1- Point
// 3-Arc
// 5-Polygon
// 8-MultiPoint
double XMin;
double YMin;
double XMax;
double YMax;
int[] Unused3 = new int[8];
}

class ESRI_ShapeFile
{
int FileCode; //9994
int[] Unused = new int[5];
int FileLength;
int Version; //1000
int ShapeType; // 0- Null shape
// 1- Point
// 3-Arc
// 5-Polygon
// 8-MultiPoint
double XMin;
double YMin;
double XMax;
double YMax;
int[] Unused1 = new int[8];
}


class ESRI_RecordHeader
{
int RecNumber;
int ContentLength;
}

class ESRI_PointContent
{
int ShapeType;
double X;
double Y;
}
class ESRI_IndexRec//索引文件
{
int Offset;
int ContentLen;
}

class ESRI_ArcContent
{
int ShapeType;
double xmin;
double ymin;
double xmax;
double ymax;
int NumParts;
int NumPoints;
}

class ESRI_PolygonContent
{
int ShapeType;
double xmin;
double ymin;
double xmax;
double ymax;
int NumParts;
int NumPoints;
}

public bool LoadShapeFile(CGDataAdapter.CGLocalGeoDataAdapter adapter)
{

string connectionString;
OdbcConnection connection;
OdbcDataAdapter OdbcAdapter;


CGMap.CGGeoLayer geolayer = adapter.getMasterGeoLayer();

string shpfilepath = adapter.getPath();
string shpfilename = adapter.getFileName();
string shxfilepath = shpfilepath.Substring(0, https://www.doczj.com/doc/9118953270.html,stIndexOf("\\") + 1) + adapter.getFileName() + ".shx";

//read out the layer attribute infomation
connectionString = "Dsn=Visual FoxPro Database;sourcedb=" + shpfilepath + ";sourcetype=DBF;exclusive=No;backgroundfetch=Yes;collate=Machine";
connection = new OdbcConnection(connectionString);
connection.Open();
OdbcAdapter = new OdbcDataAdapter("select * from " + shpfilename, connectionString);

// Create new DataTable and DataSource objects.
DataSet ds = new DataSet();
OdbcAdapter.Fill(ds);
connection.Close();

if (geolayer == null) return false;

try
{
//先读取.shx文件,得到文件的总字节长度
FileStream fs = new FileStream(shxfilepath, FileMode.Open, FileAccess.Read); //文件流形式
BinaryReader BinaryFile = new BinaryReader(fs); //二进制读取文件的对象
long BytesSum = fs.Length; //得到文件的字节总长
int shapecount = (int)(BytesSum - 100) / 8; //得以总记录数目

BinaryFile.Close();
fs.Close();

//打开shp文件
if (shxfilepath == "")
{
// MessageBox.Show("索引文件打开出错");
return false;
}
//打开.shp文件,读取x,y坐标的信息
fs = new FileStream(shpfilepath, FileMode

.Open, FileAccess.Read); //文件流形式
BinaryFile = new BinaryReader(fs); //打开二进制文件

BinaryFile.ReadBytes(32); //先读出36个字节,紧接着是Box边界合
int shapetype = BinaryFile.ReadInt32();

geolayer.envlope.left = BinaryFile.ReadDouble(); //读出整个shp图层的边界合
geolayer.envlope.bottom = BinaryFile.ReadDouble();
geolayer.envlope.right = BinaryFile.ReadDouble();
geolayer.envlope.top = BinaryFile.ReadDouble();


BinaryFile.ReadBytes(32); // shp中尚未使用的边界盒


//Get Shape Data From Here On
int stype;
double x, y;
double left, right, top, bottom;

int partcount;
int pointcount;

switch (shapetype)
{
case 1://single point

geolayer.shapeType = CGConstants.CGShapeType.SHAPE_POINT;
for (int i = 0; i < shapecount; i++)
{
CGGeoShape.CGGeoPoint gps = new CGGeoShape.CGGeoPoint();

BinaryFile.ReadBytes(12); //记录头8个字节和一个int(4个字节)的shapetype

/* stype = BinaryFile.ReadInt32();

if (stype != shapetype)
continue;

*/
x = BinaryFile.ReadDouble();
y = BinaryFile.ReadDouble();

gps.objectID = i;
gps.objectUID = i;

gps.x = x;
gps.y = y;
gps.z = 0;
gps.envlope.left = gps.x;
gps.envlope.right = gps.x;
gps.envlope.top = gps.y;
gps.envlope.bottom = gps.y;
geolayer.getDataContainer().Add(gps);
}
break;

case 8://multi points layer
break;

case 3://Polyline layer
geolayer.shapeType = CGConstants.CGShapeType.SHAPE_LINE;

for (int i = 0; i < shapecount; i++)
{
geolayer.getAttributeContainer().Add(ds.Tables[0].Rows[i][0]); //read out the attribute step by step

BinaryFile.ReadBytes(12);

// int pos = indexRecs[i].Offset+8;
// bb0.position(pos);
// stype = bb0.getInt();
// if (stype!=nshapetype){
// continue;
// }

left = BinaryFile.ReadDouble();
bottom = BinaryFile.ReadDouble();
right = BinaryFile.ReadDouble();
top = BinaryFile.ReadDouble();

partcount = BinaryFile.ReadInt32();
pointcount = BinaryFile.ReadInt32();

int[] parts = new int[partcount];
int[] partspos = new int[partcount];

double[] xpoints = new double[pointcount];
double[] ypoints = new double[pointcount];
double[] zpoints = new double[pointcount];

//firstly read out parts begin pos in file
for (int j = 0; j < partcount; j++)
{
parts[j] = BinaryFile.ReadInt32();
}
//shift them to be points count included in parts
if (partcount > 0)
partspos[0] = 0;

int newpos = 0;
for (int j = 0; j <= partcount - 2; j++)
{
parts[j] = parts[j + 1] - parts[j];
newpos += parts[j];
partspos[j + 1] = newpos;
}

parts[partcount - 1] = pointcount - parts[partcount - 1];

//read out coordinates
for (int j = 0; j < pointcount; j++)
{
x = BinaryFile.ReadDouble();
y = BinaryFile.ReadDouble();
xpoints[j] = x;
ypoints[j] = y;
zpoints[j] = 0;
}
if (pointcount > 1)
{
CGGeoShape.CGGeoLine gl = new CGGeoShape.CGGeoLine(xpoints, ypoints, zpoints, parts, partspos, pointcount, partcount);
gl.envlope.left = left;


gl.envlope.right = right;
gl.envlope.top = top;
gl.envlope.bottom = bottom;

gl.objectID = i;
gl.objectUID = i;
geolayer.getDataContainer().Add(gl);

}
}
break;

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