public static extern int DBFAddFieldW(IntPtr hDBF, string szFieldName, DBFFieldType eType, int nWidth, int nDecimals);
public static extern int DBFAddField(IntPtr hDBF, string szFieldName, DBFFieldType eType, int nWidth, int nDecimals);
public static extern int DBFAddFieldW(IntPtr hDBF, string szFieldName, DBFFieldType eType, int nWidth, int nDecimals);
public static extern int DBFAddField(IntPtr hDBF, string szFieldName, DBFFieldType eType, int nWidth, int nDecimals);