if strField <> '' then
with Table1.FieldByName(strField) do
if (DataType = ftString) or (DataType = ftMemo) then
strQuote := '"' else
strQuote := '';
{ Construct the WHERE clause of the query based on the user's choice
in Type. }
case etSQLOps(ComboBox1.ItemIndex) of
soNoCondition: strWhere := '';
soEqual: strWhere := strField ' = ' strQuote strValue strQuote;
soNotEqual: strWhere := strField ' <> ' strQuote strValue
strQuote;
soLessThan: strWhere := strField ' < ' strQuote strValue
strQuote;
soLessEqual: strWhere := strField ' <= ' strQuote strValue
strQuote;
soMoreThan: strWhere := strField ' > ' strQuote strValue
strQuote;
soMoreEqual: strWhere := strField ' >= ' strQuote strValue
strQuote;
soStartsWith: strWhere := strField ' LIKE ' strQuote
strValue '%' strQuote;
soNoStartsWith: strWhere := strField ' NOT LIKE ' strQuote
strValue '%' strQuote;
soEndsWith: strWhere := strField ' LIKE ' strQuote
'%' strValue strQuote;
soNoEndsWith: strWhere := strField ' NOT LIKE '
strQuote '%' strValue strQuote;
soContains: strWhere := strField ' LIKE ' strQuote '%' strValue
'%' strQuote;
soNoContains: strWhere := strField ' NOT LIKE ' strQuote '%'
strValue '%' strQuote;
soBlank: strWhere := strField ' IS NULL';
soNotBlank: strWhere := strField ' IS NOT NULL';
end;
if ComboBox1.ItemIndex = Ord(soNoCondition) then
strQuery := 'SELECT * FROM "' strTable '"'
else if Table1.FieldByName(strField).DataType = ftString then
strQuery := 'SELECT * FROM "' strTable '" t WHERE t.' strWhere
else
strQuery := 'SELECT * FROM "' strTable '" t WHERE t.' strWhere;
{ Create an instance of the browser form. }
frmQuery := TResultForm.Create(Application);
{ Use a resource protection block in case an exception is raised. This
ensures that the memory allocated for the Results form is released. }
try
with frmQuery do
begin
Screen.Cursor := crHourglass;
if Query1.Active then Query1.Close;
Query1.DatabaseName := strAlias; {set the alias the query poitns to}
Query1.SQL.clear; { empty existing SQL in the query }
Query1.SQL.Add(strQuery); { add query string to query object }
Query1.Active := True; { try to run the query }
Screen.Cursor := crDefault;
if Query1.Active then
begin
{ If the query didn't return any records, there's no point in
displaying the form. In that event, raise an exception. }
if Query1.RecordCount < 1 then
raise Exception.create('No records matched your criteria.
Please try again.' );
{ write a message to the browse form's status line }
if strField = '' then
Panel3.Caption := 'Now showing all records from ' strTable
'...'
else
Panel3.Caption := 'Now showing ' strTable ' where ' strField
' contains values equal to ' strValue '...';
{ show the form }
ShowModal;
end;
end;
finally
frmQuery.Free;
end;
end;
end.
unit RSLTFORM;
interface
uses
SysUtils, Windows, Messages, Classes, Graphics, Controls, StdCtrls, DB,
Forms, DBCtrls, DBGrids, DBTables, Buttons, Grids, ExtCtrls, Dialogs;
type
TResultForm = class(TForm)
DBGrid1: TDBGrid;
DBNavigator: TDBNavigator;
Panel1: TPanel;
DataSource1: TDataSource;
Panel2: TPanel;
Panel3: TPanel;
Query1: TQuery;
SpeedButton2: TSpeedButton;
Panel4: TPanel;
SpeedButton1: TSpeedButton;
procedure SpeedButton1Click(Sender: TObject);
procedure SpeedButton2Click(Sender: TObject);
end;
var
ResultForm: TResultForm;
implementation
{$R *.DFM}
procedure TResultForm.SpeedButton1Click(Sender: TObject);
begin
Close;
end;
procedure TResultForm.SpeedButton2Click(Sender: TObject);
var
strText: string; { Variable to hold display text }
iCounter: Integer; { Loop counter variable }
begin
{ Build a string containing the query }
strText := '';
for iCounter := 0 to Query1.SQL.Count - 1 do
strText := strText Query1.SQL[iCounter];
{ Display the query text }
MessageDlg('The underlying query is: ' #10 #10 strText,
mtInformation, [mbOK], 0 );
end;
end.
上一篇： Delphi客户服务器应用开发（一）
文章整理：西部数码--专业提供域名注册、虚拟主机服务
http://www.west263.com
以上信息与文章正文是不可分割的一部分,如果您要转载本文章,请保留以上信息，谢谢!
