osgearth2.10用gdal读取S57地图的代码

以下是使用GDAL库读取S57地图的代码示例：

#include <iostream>
#include <gdal_priv.h>
#include <ogrsf_frmts.h>

int main() {
    GDALAllRegister();

    // 输入S57文件路径
    const char* filePath = "path/to/s57/file";

    // 打开S57文件
    GDALDataset* dataset = (GDALDataset*)GDALOpenEx(filePath, GDAL_OF_READONLY | GDAL_OF_VECTOR, NULL, NULL, NULL);

    if (dataset == NULL) {
        std::cout << "Failed to open S57 file." << std::endl;
        return 1;
    }

    // 获取第一个图层
    OGRLayer* layer = dataset->GetLayer(0);

    if (layer == NULL) {
        std::cout << "Failed to get layer." << std::endl;
        GDALClose(dataset);
        return 1;
    }

    // 输出图层属性信息
    OGRFeatureDefn* featureDefn = layer->GetLayerDefn();
    std::cout << "Layer Name: " << featureDefn->GetName() << std::endl;
    std::cout << "Field Count: " << featureDefn->GetFieldCount() << std::endl;

    // 逐个读取图层要素
    OGRFeature* feature = NULL;
    layer->ResetReading();

    while ((feature = layer->GetNextFeature()) != NULL) {
        // 获取要素几何信息
        OGRGeometry* geometry = feature->GetGeometryRef();
        if (geometry != NULL) {
            // 输出要素几何信息
            std::cout << "Geometry Type: " << geometry->getGeometryName() << std::endl;
        }

        // 获取要素属性信息
        OGRFeatureDefn* featureDefn = layer->GetLayerDefn();
        int fieldCount = featureDefn->GetFieldCount();

        for (int i = 0; i < fieldCount; ++i) {
            OGRFieldDefn* fieldDefn = featureDefn->GetFieldDefn(i);
            std::cout << fieldDefn->GetNameRef() << ": " << feature->GetFieldAsString(i) << std::endl;
        }

        // 释放要素内存
        OGRFeature::DestroyFeature(feature);
    }

    // 关闭S57文件
    GDALClose(dataset);

    return 0;
}

该代码主要使用了GDAL库和OGR库，首先通过GDALOpenEx函数打开S57文件，然后获取第一个图层并输出其属性信息，最后逐个读取图层要素，输出要素的几何信息和属性信息，释放内存并关闭文件。