- (char) fieldType: (NSInteger) fieldno;

The function fieldType() returns a type of a field by index.
There are following types:

• C - Character
• N - Numeric
• F - Float
• L - Logical
• D - Date
• M - Memo
• G - General
• T - DateTime
• I - Integer
• Y - Currency
• B - Double
• @ - TimeStamp
• O - Inverted Double
• V - Variant
• Q - VarBinary
• W - Blob
• + - Autoincrement
• 0 - System

{
    // your code
    for (NSInteger i=0; i < [dbf fieldCount]; i++)
        NSLog(@"%c", [dbf fieldType:i] );
    // your code
}