[Shapelib] C# wrapper around DBFReadIntegerAttribute.

[C S]

hi all! 

i hope someone somewhere out there is or has tried to
to do some C# stuff around the C API. 

i wrote a C++ program to read a SHP and DBF file and
get the attributes from a certain column and then
tried the same thing using a basic C# wrapper. most
things seem to work fine but DBFRead**Attribute stuff
just doesnt seem to work.  here is my code for
re-writing the DBF struct(not headers in C#) and my
extern statement. 

[StructLayout(LayoutKind.Sequential)]
	public struct DBFInfo
	{
		public IntPtr   fp;
		public int      nRecords;
		public int	nRecordLength;
		public int	nHeaderLength;
		public int	nFields;
		public IntPtr	panFieldOffset;
		public IntPtr	panFieldSize;
		public IntPtr	panFieldDecimals;
		public string   pachFieldType;
		public string   pszHeader;
		public int	nCurrentRecord;
		public int	bCurrentRecordModified;
		public string   pszCurrentRecord;
		public int	bNoHeader;
		public int      nBufSize;
	};

[DllImport("shapelib.dll", EntryPoint =
"DBFReadIntegerAttribute")]
public static extern int
DBFReadIntegerAttribute(DBFInfo myDBFHandle, int
shape, int field);

i am using the shapelib.dll from the folder
shapelib(vc7.1) that i downloaded. i am using by the
way Visual Studio .NET 2003(does this make any
difference?).

then in a function i try to call this function to get
the values in a loop of all the fields. 
/**************************************************
//in some function:

int shape_total = 0;
int *width = null
int *decimals = null;
int total_matches = 0;
string fieldName = "";

public static unsafe int population(IntPtr SPtr,
IntPtr DPtr, SHPInfo Shandle, DBFInfo Dhandle)
{
 for(int i = 0; i < Dhandle.nFields; i++)
 {
  outfile.Write(DBFGetFieldInfo(Dhandle, i+1, out
fieldName, out width, out decimals)); 
  outfile.Write(" name: ");
  outfile.WriteLine(fieldName);
 }
}

in my output for every field i am always getting
FTInvalid and fieldName is always blank. upon
debugging and looking at my local watches right after
i do the first DBFGetFieldInfo call here are the list
of watches under Dhandle and their values, with their
types: 

bCurrentRecordModified	0	int
bNoHeader	0	int
fp	268766432	int
nBufSize	0	int
nCurrentRecord	-1	int
nFields	101	int
nHeaderLength	3265	int
nRecordLength	926	int
nRecords	28	int
pachFieldType
"NNNNNNCCNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNýýýý"
string
panFieldDecimals	48530680	int	panFieldOffset	48521256
int	
panFieldSize	48530232	int
pszCurrentRecord
"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍýýýý"
string
pszHeader	"AREA"	string

the number of fields, records, the header string and
record length are all correct and match up well the
C++ output i am getting in the watches their. but
notice nCurrentRecord is -1 and the decimals, offset
and pszCurrentRecord are showing crazy stuff. the
pszCurrent record in the visual studio debugging tool
is nice enough to show you ALL the fields values..in
C++ its correct, in C# i get these weird 'I'
characters. maybe because nCurrentRecord is -1
somehow? 

i am at my wits end. the SHP functions work just fine.


is there anything i could try? can anyone offer any
pointers? 



       
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