GDAL读取查询shp数据

用GDAL读取shp数据都是基于OGR库的,需要提前编译好GDAL库,配置好环境变量。这里的代码是在Linux系统下基于Qt5编写和运行的,亲测能成功运行。GDAL编译可以查看之前的文档,代码及部分说明如下:

#include "widget.h"
#include <QApplication>
#include "gdal.h"
#include "gdal_priv.h"
#include "ogrsf_frmts.h"
#include <iostream>
#include <QDebug>
#include <QString>
#include <vector>
#include <QVector>

using namespace std;

int main(int argc, char *argv[])
{
    GDALAllRegister();
    GDALDataset *poDS;
//    CPLSetConfigOption("SHAPE_ENCODING","");  //解决乱码问题,建议注释掉
    //read shp files
    poDS=(GDALDataset*) GDALOpenEx("train_data/station_point.shp",GDAL_OF_VECTOR,NULL,NULL,NULL);

    if(poDS==NULL)
    {
        return 0;
    }

    OGRLayer *poLayer;
//    poLayer=poDS->GetLayer(0); //获取图层
    poLayer=poDS->GetLayerByName("station_point");  //通过名字获取突出
    QVector<QString> strVector;
    OGRFeature *poFeature;
    poLayer->ResetReading();
    while((poFeature=poLayer->GetNextFeature())!=NULL)
    {
        OGRFeatureDefn *poFDefn=poLayer->GetLayerDefn();
        int iField;
        int n=poFDefn->GetFieldCount(); //得到字段数目,不包括最前面的两个字段(FID,shape),在arcgis里面这两个字段不能被改变
        for(iField=0;iField<n;iField++)
        {
            OGRFieldDefn *poFieldDefn=poFDefn->GetFieldDefn(iField);
            //output every field's value
            if(poFieldDefn->GetType()==OFTInteger){
//                qDebug()<<poFeature->GetFieldAsInteger(iField);  //用qDebug输出,类似cout
//                qDebug("%d",poFeature->GetFieldAsInteger(iField)); //输出,不同的形式,效果与上句相同
            }
            else if(poFieldDefn->GetType()==OFTReal){
//                qDebug()<<poFeature->GetFieldAsDouble(iField);
//                qDebug("%.3f",poFeature->GetFieldAsDouble(iField));
            }
            else if(poFieldDefn->GetType()==OFTString){
//                qDebug()<<poFeature->GetFieldAsString(iField);
//                qDebug("%s",poFeature->GetFieldAsString(iField));

                strVector.push_back(poFeature->GetFieldAsString(iField)); //用了一个容器将name存到容器中
            }
            else{
//                qDebug()<<poFeature->GetFieldAsString(iField);
//                qDebug("%s",poFeature->GetFieldAsString(iField));

//                strVector.push_back(poFeature->GetFieldAsString(iField));
            }
//            qDebug()<<poFeature->GetFieldAsString(iField)<<"  ";
//            qDebug()<<poFeature->GetFieldAsString(iField);

        }
        
        for(int i=0;i<strVector.size();i++)
        {
            qDebug()<<strVector[i];
        }
        qDebug()<<strVector.size();
        OGRFeature::DestroyFeature(poFeature);
    }
    GDALClose(poDS);
    system("pause");


    QApplication a(argc, argv);
//    Widget w;
//    w.show();
    
    return a.exec();
}
因为用到了qDebug,需要配置一下,参考 https://blog.csdn.net/qq_38378235/article/details/80653092







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转载自blog.csdn.net/qq_38378235/article/details/80656955