如何知道字段的属性？

我想知道某个字段是数字类型还是字符串类型，应该怎样做呢？ 问题点数：20、回复次数：5Top

1 楼fengzhengren（风筝）回复于 2005-06-01 15:19:30 得分 10

用GetEnumName得到。  
   
  uses    
      TypInfo;  
   
  放一个TQuery，连接到数据库，SQL:   'select   *   from   Table1'  
  procedure   TForm1.Button1Click(Sender:   TObject);  
  var  
          i:integer;  
  begin  
          Query1.Open;  
          for   i:=0   to   Query1.FieldCount-1   do  
                  Memo1.Lines.Add(Query1.Fields[i].FieldName+':'+GetEnumName(TypeInfo(TFieldType),Integer(Query1.Fields[i].DataType))+':'+IntToStr(Query1.Fields[i].DataSize));  
          Query1.Close;  
  end;  
  Top

2 楼wenjianyao（建）回复于 2005-06-01 15:45:18 得分 2

呵呵，帮顶Top

3 楼hansonboy（hansonboy）回复于 2005-06-01 16:38:49 得分 0

数据库是SQL   server2000怎么不行的Top

4 楼hansonboy（hansonboy）回复于 2005-06-02 11:45:20 得分 0

upTop

5 楼cimssoft（楚狂客）回复于 2005-06-02 12:04:20 得分 8

直接使用Fields[i].DataType  
   
  其中  
  property   DataType:   TFieldType;  
   
  TFieldType在delphi的帮助文件中有描述的，这里帮你贴一下  
   
  Value Description  
  -----------------------------------------------------------  
  ftUnknown               Unknown   or   undetermined  
  ftString                 Character   or   string   field  
  ftSmallint             16-bit   integer   field  
  ftInteger               32-bit   integer   field  
  ftWord               16-bit   unsigned   integer   field  
  ftBoolean               Boolean   field  
  ftFloat               Floating-point   numeric   field  
  ftCurrency             Money   field  
  ftBCD               Binary-Coded   Decimal   field   that   can   be   converted   to   Currency   type     without   a   loss   of   precision.  
  ftDate               Date   field  
  ftTime               Time   field  
  ftDateTime             Date   and   time   field  
  ftBytes               Fixed   number   of   bytes   (binary   storage)  
   
  ftVarBytes             Variable   number   of   bytes   (binary   storage)  
  ftAutoInc               Auto-incrementing   32-bit   integer   counter   field  
  ftBlob               Binary   Large   OBject   field  
  ftMemo               Text   memo   field  
  ftGraphic               Bitmap   field  
  ftFmtMemo               Formatted   text   memo   field  
  ftParadoxOle Paradox   OLE   field  
  ftDBaseOle dBASE   OLE   field  
  ftTypedBinary Typed   binary   field  
  ftCursor                   Output   cursor   from   an   Oracle   stored   procedure   (TParam   only)  
  ftFixedChar Fixed   character   field  
  ftWideString Wide   string   field  
  ftLargeint Large   integer   field  
   
  ftADT                   Abstract   Data   Type   field  
  ftArray                   Array   field  
  ftReference REF   field  
  ftDataSet                   DataSet   field  
  ftOraBlob BLOB           fields   in   Oracle   8   tables  
  ftOraClob CLOB           fields   in   Oracle   8   tables  
  ftVariant   Data   of   unknown   or   undetermined   type  
  ftInterface References   to   interfaces   (IUnknown)  
  ftIDispatch References   to   IDispatch   interfaces  
  ftGuid                   globally   unique   identifier   (GUID)   values  
  ftTimeStamp Date   and   time   field   accessed   through   dbExpress  
  ftFMTBcd                   Binary-Coded   Decimal   field   that   is   too   large   for   ftBCD.Top

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• 32-bit
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