如何获取MySQL查询的结果以显示在cxGrid中？

如何解决如何获取MySQL查询的结果以显示在cxGrid中？

我正在使用Delphi 5，我想在cxGrid中显示MySQL查询的结果。我将cxGrid，cxGridLevel和cxGridDBTableView设置为添加到表单时的默认设置。 cxGridDBTableView的DataController.DataSource是一个名为DSNewKits的TDataSource，其DataSet设置为一个名为NewKitsQry的tMySQLQuery。

当需要显示数据时，我将DSNewKits的Enabled属性设置为false，运行NewKitsQry的Close方法，然后将DSNewKits的Enabled属性设置为true，将NewKitsQry的SQL.Text属性设置为，并运行打开方法NewKitsQry。然后，我有一个消息对话框，显示查询中的结果数，共有408个，因此我知道查询工作正常。网格显示的行和列之间有行，没有“没有数据要显示”消息，但所有单元格均为空白。

我尝试以不同的顺序执行这些步骤，注释掉其中的某些内容，依此类推，但是没有什么可以显示数据。我确定我遗漏了一些简单和/或显而易见的内容，但无法在线找到示例。谢谢您能提供的任何帮助！

（编辑为包含代码）这是我的代码：


interface

uses
  Windows,Messages,SysUtils,Classes,Graphics,Controls,Forms,Dialogs,cxGridLevel,cxGridCustomTableView,cxGridTableView,cxGridDBTableView,cxClasses,cxControls,cxGridCustomView,cxGrid,ExtCtrls,Db,mySQLDbTables,ovcbase,ovcfiler,ovcstore,gECCConst,StdCtrls;

type
  Tf_cw_cxgrid_db = class(TForm)
    WebCatDB: TmySQLDatabase;
    NewKitsQry: TmySQLQuery;
    DSNewKits: TDataSource;
    Panel1: TPanel;
    cxNewKitsGrid: TcxGrid;
    cxNewKitsGridDBTableView1: TcxGridDBTableView;
    cxNewKitsGridDBTableView1CompanyID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1RegionID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1BranchID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1CustID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1Username: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitComment: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitEffDate: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitExpDate: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitNote: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitType: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitFlags: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitTab: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitAddDate: TcxGridDBColumn;
    cxNewKitsGridDBTableView1KitEditedDate: TcxGridDBColumn;
    cxNewKitsGridDBTableView1Line: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ProductID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1MfgProdID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1PartNum: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ProductDesc: TcxGridDBColumn;
    cxNewKitsGridDBTableView1Qty: TcxGridDBColumn;
    cxNewKitsGridDBTableView1RefQty: TcxGridDBColumn;
    cxNewKitsGridDBTableView1UnitPrice: TcxGridDBColumn;
    cxNewKitsGridDBTableView1UnitPriceType: TcxGridDBColumn;
    cxNewKitsGridDBTableView1UofM: TcxGridDBColumn;
    cxNewKitsGridDBTableView1PSUofM: TcxGridDBColumn;
    cxNewKitsGridDBTableView1UNSPSC: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ItemNote: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ItemGroupID: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ItemDrpDnHdr: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ItemSection: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ItemFlags: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ItemAddDate: TcxGridDBColumn;
    cxNewKitsGridDBTableView1ItemEditedDate: TcxGridDBColumn;
    cxNewKitsGrid1Level1: TcxGridLevel;
    RegistryStore: TOvcRegistryStore;
    userqry: TmySQLQuery;
    Button1: TButton;
    procedure FormShow(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  f_cw_cxgrid_db: Tf_cw_cxgrid_db;

implementation

{$R *.DFM}

procedure Tf_cw_cxgrid_db.FormShow(Sender: TObject);
var
  Server : String;
  User   : String;
  Passwd : String;
  DBName : String;
  Button : Integer;
  WCPath : String;
begin
  RegistryStore.Open;
  Server     := RegistryStore.ReadString( 'SBAdmin','Host','127.0.0.1');
  User       := RegistryStore.ReadString( 'SBAdmin','User','');
  Passwd     := RegistryStore.ReadString( 'SBAdmin','Password','');
  DBName     := RegistryStore.ReadString( 'SBAdmin','Database',WebCatDefUserDBName );  { caw 7-24-20 }
  RegistryStore.Close;

  WebCatDB.Host              := Server;
  WebCatDB.UserName          := User;
  WebCatDB.UserPassword      := Passwd;
  WebCatDB.DatabaseName      := 'WEBCAT_' + DBName;
end;

procedure Tf_cw_cxgrid_db.Button1Click(Sender: TObject);
begin
  DSNewKits.Enabled := False;
  NewKitsQry.Close;
  try
    DSNewKits.Enabled := True;
    NewKitsQry.SQL.Text := 'SELECT KitHdrs.CompanyID,KitHdrs.RegionID,KitHdrs.BranchID,KitHdrs.CustID,' +
                           'KitHdrs.Username,KitHdrs.KitID,KitHdrs.KitComment,KitHdrs.KitEffDate,' +
                           'KitHdrs.KitExpDate,KitHdrs.KitNote,KitHdrs.KitType,KitHdrs.KitFlags,KitHdrs.KitTab,' +
                           'KitHdrs.KitAddDate,KitHdrs.KitEditedDate,KitLines.Line,KitLines.ProductID,' +
                           'KitLines.MfgProdID,KitLines.PartNum,KitLines.ProductDesc,KitLines.Qty,' +
                           'KitLines.RefQty,KitLines.UnitPrice,KitLines.UnitPriceType,KitLines.UofM,' +
                           'KitLines.PSUofM,KitLines.UNSPSC,KitLines.ItemNote,KitLines.ItemGroupID,' +
                           'KitLines.ItemDrpDnHdr,KitLines.ItemSection,KitLines.ItemFlags,' +
                           'KitLines.ItemAddDate,KitLines.ItemEditedDate ' +
                           'FROM KitHdrs JOIN KitLines ON KitHdrs.KitSeq = KitLines.KitSeq;';
    NewKitsQry.Open;
    cxNewKitsGridDBTableView1.DataController.CreateAllItems;

    MessageDlg( 'There are ' + IntToStr( NewKitsQry.RecordCount ) + ' records.',mtInformation,[mbOK],0 );
  except
    MessageDlg( 'There was an error displaying the kit databases.',mtError,0 );
  end;
end;

end.

解决方法

尽管cxGrid是一个很好的组件，但事实是它有很多深层的嵌套属性会使从头开始设置cxGrid变得相当艰巨。

我创建了以下示例，以展示如何完全在代码中创建和设置cxGrid 这样您就可以轻松看到需要完成的最低要求。它使用了TClientDataSet 用代码填充，以提供网格数据，从而使示例完全独立。使其适应现有的MySql将变得微不足道数据集。

type
  TForm1 = class(TForm)
    CDS1: TClientDataSet;
    DS1: TDataSource;
    DBNavigator1: TDBNavigator;
    Button1: TButton;
    procedure FormCreate(Sender: TObject);
  private
  protected
  public
    cxGrid : TcxGrid;
    cxLevel : TcxGridLevel;
    cxView : TcxGridDBTableView;
  end;
[...]
// This is a utility function to create TFields in code
function CreateField(AFieldClass : TFieldClass; AOwner : TComponent; ADataSet : TDataSet;
AFieldName,AName : String; ASize : Integer; AFieldKind : TFieldKind) : TField;
begin
  Result := AFieldClass.Create(AOwner);
  Result.FieldKind := AFieldKind;
  Result.FieldName := AFieldName;
  Result.Name := AName;
  Result.Size := ASize;
  Result.DataSet := ADataSet;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  i : Integer;
  Field : TField;
begin
  //  All the code to set up the cxGrid is in this event handler
  
  //  First,create the Fields of the ClientDataSet
  Field := CreateField(TIntegerField,Self,CDS1,'ID','CDS1ID',fkData);
  Field := CreateField(TIntegerField,'Qty','CDS1Qty',fkData);
  Field := CreateField(TCurrencyField,'UnitPrice','CDS1UnitPrice',fkData);
  CDS1.CreateDataSet;

  CDS1.IndexFieldNames := 'ID';

  //  Next,populate the CDS with a few records
  CDS1.InsertRecord([1,1,1]);
  CDS1.InsertRecord([2,2,5]);
  CDS1.InsertRecord([3,3,6]);

  CDS1.First;

  DS1.DataSet := CDS1;

  //  Now,create a cxGrid to display the CDS data
  cxGrid := TcxGrid.Create(Self);
  cxGrid.Parent := Self;
  cxGrid.Width := 400;

  cxLevel := cxGrid.Levels.Add;
  cxLevel.Name := 'Firstlevel';

  cxView := cxGrid.CreateView(TcxGridDBTableView) as TcxGridDBTableView;
  cxView.Name := 'ATableView';
  cxView.DataController.KeyFieldNames := 'ID';

  cxLevel.GridView := cxView;
  cxView.DataController.DataSource := DS1;
  cxView.DataController.CreateAllItems;
end;

如何获取MySQL查询的结果以显示在cxGrid中？

如何解决如何获取MySQL查询的结果以显示在cxGrid中？

解决方法

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