/// <summary>
/// 读取指定行列号的数据
/// </summary>
/// <param name="level"></param>
/// <param name="row"></param>
/// <param name="col"></param>
/// <returns></returns>
public Byte[] Read(int level, int row, int col)
{
string bundleFilePath = GetBundleFileWithouExtention(level, row, col);
// 打开对应的索引文件
EsriBundleIndexFile indexFile = new EsriBundleIndexFile(bundleFilePath + EsriBundleFileConfig.BundleIndexExt);
indexFile.Intiliaze();
// 读取所有索引
var bundleIndices = indexFile.GetAllIndices();
// 读取数据文件
EsriBundleFile dataFile = new EsriBundleFile(bundleFilePath + EsriBundleFileConfig.BundleExt, bundleIndices);
dataFile.Intiliaze();
int index;
EsriBundleHelper.ComputeIndex(row, col, PacketSize, out index);
var tileBytes = dataFile.Read(index);
indexFile.Dispose();
dataFile.Dispose();
return tileBytes;
}
static void CreateIndexFile(string oldfilepath, string newfilepath)
{
EsriBundleIndexFile indexfile = new EsriBundleIndexFile(oldfilepath);
indexfile.Intiliaze();
//indexfile.SaveAs(newfilepath);
EsriBundleIndexFile indexfile1 = new EsriBundleIndexFile(indexfile.GetAllIndices());
indexfile1.Intiliaze();
indexfile1.SaveAs(newfilepath);
indexfile1.Dispose();
indexfile.Dispose();
}
public void NewFileModeSaveAs(string newDataPath, Dictionary<int, byte[]> tilesBytesDict)
{
Config.NotNullTileCount = tilesBytesDict.Count;
Config.MaxTileSize = 0;
IList<TileIndex> allIndices = new List<TileIndex>();
using (Stream newDataStream = new FileStream(newDataPath, FileMode.CreateNew))
{
// 写入所有数据的空数据位置，每个4字节，空数据按其索引指向此位置
newDataStream.Seek(EsriBundleFileConfig.HeaderSize, SeekOrigin.Begin);
newDataStream.Write(new byte[EsriBundleFileConfig.MaxTileCount * 4], 0, EsriBundleFileConfig.MaxTileCount * 4);
for (int i = 0; i < EsriBundleFileConfig.MaxTileCount; i++)
{
byte[] dataBytes = null;
tilesBytesDict.TryGetValue(i, out dataBytes);
// 数据为空,只写入4个字节的长度，表示0
if (dataBytes == null)
{
//计算索引位置，位于空数据位置
allIndices.Add(new TileIndex()
{
Number = i,
Offset = EsriBundleFileConfig.HeaderSize + 4 * i
});
}
else
{
//生成有数据的文件索引
allIndices.Add(new TileIndex()
{
Number = i,
Offset = newDataStream.Position
});
//写入数据的大小和数据本身
newDataStream.Write(BitConverter.GetBytes(dataBytes.Length), 0, 4);
newDataStream.Write(dataBytes, 0, dataBytes.Length);
if (Config.MaxTileSize < dataBytes.Length)
{
Config.MaxTileSize = dataBytes.Length;
}
}
}
WriteHeaderBytes(newDataStream);
}
//同时生成索引文件
EsriBundleIndexFile indexFile = new EsriBundleIndexFile(allIndices);
indexFile.Intiliaze();
string newIndexPath = Path.ChangeExtension(newDataPath, EsriBundleFileConfig.BundleIndexExt);
indexFile.SaveAs(newIndexPath);
indexFile.Dispose();
indexFile = null;
}