如何取得指定表中的列的类型

[cghdenglu]

在连上数据库,但没有生成数据集时,如何取得指定表中的列的类型

[jbzj]

我帮你顶上一下

[zhangnan623]

关注

[fenger521]

借个地方，也是没办法

有哪位大虾看了　李维-delphi7高效数据库程序设计　书上说的光盘里的数据库在哪？小弟可是花了不少米米才下决心买的呀，两张光盘，第一张且不说，第二张除了十几兆的示例文件，什么都没有，连　*.GDB也没有　？？？？　
谁有?　帮帮小弟.　　[e-mail] 万分感谢！！
http://expert.csdn.net/Expert/topic/2526/2526666.xml?temp=.1381037
这个页面，马上给分，不够可以加。

[ghchen]

怎么没有人回答这个问题呀，我也想知道呀

[hacking]

ADOConnection.GetTableNames(combobox4.Items,false); false表示不要系统表,TRUE表示要系统表
adotable.GetFieldNames(combobox1.items);获得表的所有字段.
adotable.FieldByName('XXXX').DataType是该字段的类型
adotable.FieldByName().Size是该字段的长度
你已经获得了表和字段名,想要什么直接从TField找好了.

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, DB, ADODB;

type
TForm1 = class(TForm)
ADOConnection1: TADOConnection;
ADOQuery1: TADOQuery;
Memo1: TMemo;
Button1: TButton;
ListBox1: TListBox;
Button2: TButton;
Table: TMemo;
ComboBox1: TComboBox;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
Try
//....
//ADOQuery1.Open;
ADOConnection1.GetTableNames(ListBox1.Items);
Except
end;
end;

procedure TForm1.Button2Click(Sender: TObject);
Procedure GetTableFieldInfo;
var
vIndex : Integer;
vDataType : String;
begin
Memo1.Clear;
for vIndex := 0 to ComboBox1.Items.Count -1 do
Memo1.Lines.Add(IntToStr(TField(ComboBox1.Text).Size));
Case TField(ComboBox1.Text).DataType of
ftString : vDataType := '字符型';
//....
end;
Memo1.Lines.Add('数据类型为：' + vDataType);
end;
{
TFieldType = (ftUnknown, ftString, ftSmallint, ftInteger, ftWord,
ftBoolean, ftFloat, ftCurrency, ftBCD, ftDate, ftTime, ftDateTime,
ftBytes, ftVarBytes, ftAutoInc, ftBlob, ftMemo, ftGraphic, ftFmtMemo,
ftParadoxOle, ftDBaseOle, ftTypedBinary, ftCursor, ftFixedChar, ftWideString,
ftLargeint, ftADT, ftArray, ftReference, ftDataSet, ftOraBlob, ftOraClob,
ftVariant, ftInterface, ftIDispatch, ftGuid, ftTimeStamp, ftFMTBcd);

}
begin
if ListBox1.ItemIndex = -1 then
Exit;
with ADOQuery1 do
begin
if Active then
Active := False;
SQL.Clear;
SQL.Add('Select * From ' + ListBox1.Items[ListBox1.ItemIndex] );
Prepared;
Open;
GetFieldNames(ComboBox1.Items);
GetTableFieldInfo;
end;
end;

end.

[linjie208]

procedure TFDemo.Button2Click(Sender: TObject);
var
YourFieldType:string;
ATableName:string;
begin
ATableName:='T_B_Unit';
adoquery1.SQL.text := 'select FieldName=left(a.name,255) ,'
+' DataTypeName=left(b.name,255),'
+' DataLen=a.length,'
+' CanNull=columnproperty(object_id("'+ATableName+'"),a.name,"AllowsNull"),'
+' DefaultValue=(select left(text,20) from syscomments where id= a.cdefault) '
+' from syscolumns a,systypes b '
+' where a.id=object_id("'+ATableName+'") '
+' and a.xtype=b.xtype'
+' order by a.colid';
showmessage(adoquery1.sql.Text);
adoquery1.open ;
YourFieldType:= trim(adoquery1.fieldbyname('DataTypeName').asstring) ;

[cghdenglu]

好了，感谢以上几位高手，不过Procedure GetTableFieldInfo是什么语法呀

我从来都没有看过,不能解释一下，小弟在此先谢了

[linjie208]

用到Sp_columns TabelName

[helodd]

支持 linjie208(御风而行) 的方法