[Gdal-dev] ask for technique help

[Mateusz Loskot]

chenxuexia wrote:
> hello,gdal teams.   Now i begin to  use gdal to develop a plugg-in
> for reading ArcGIS data. There's a field value showing like
> "2.3565E-06", and the field type  is displayed as float in
> ArcCatolo.

What datasource do you read?
What does the "There's" mean here - there means where,
in a database, in a shapefile?

> also displayed as figure while export to dBase. But when i
> reading it in gdal, the field type is "OFTIntegerList", 

I don't know.
Perhaps there is some bug, perhaps type is translated incorrectly.
Anyway, to be sure, more details are needed about what datasource do you
use.

> :1.  how and why do you store this "2.3565E-06" as an IntegerList?2.
> how can i reading field of this type into a CString object?3.

Where does the CString come from?
What is that?

Personally, I know 2 similar classes , ATL::CString, WTL::CString,
I bet there is one for MFC.

> which types can be readed  by GetFieldAsString() function?

Check the manual:

http://www.gdal.org/ogr/classOGRFeature.html#c7a0224e13dce1f9479a6bf2111ea766

> ////////////////////////////////// //Codes below are mine:   if(
> FieldType == OFTIntegerList || FieldType == OFTRealList ) {// how to
> put a OFTIntegerList object like "5.26521E-06"into a CString object?
>  strField.Format("%e",poFeature->GetFieldAsString(j));  //ERROR! } 

What does the %e formatter do here?

I suppose it should read %s.

Cheers
-- 
Mateusz Loskot
http://mateusz.loskot.net