FireDAC 中文字段过滤问题

时间:2022-11-14 17:19:40

当使用 FireDAC Filter  过滤数据的时候,通常这样写:

FDMemTable.Filtered := False;
FDMemTable1.Filter := '姓名=' + string(edtFilter.Text).QuotedString;
FDMemTable.Filtered := True;

将会报错:
[FireDAC][Stan][Eval]-107. Invalid character found [ 姓名 = '张三' ]

解决方法一:字段名称加上方括号[]

FDMemTable1.Filter := '[姓名]=' + string(edtFilter.Text).QuotedString;

解决方法二:通过 OnFilterRecord 事件处理

procedure TForm1.OnMyFilterRecord(DataSet: TDataSet; var Accept: Boolean);
begin
Accept := DataSet.FieldByName('姓名').AsString = edtFilter.Text;
end;

附上完整代码,如下:

unit Unit1;

interface

uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, FireDAC.Stan.Intf, FireDAC.Stan.Option, FireDAC.Stan.Param, FireDAC.Stan.Error,
FireDAC.DatS, FireDAC.Phys.Intf, FireDAC.DApt.Intf, Data.DB, FireDAC.Comp.DataSet, FireDAC.Comp.Client,
FireDAC.Stan.StorageBin, Vcl.StdCtrls, Vcl.Grids, Vcl.DBGrids; type
TForm1 = class(TForm)
grd1: TDBGrid;
ds1: TDataSource;
btnFiltered: TButton;
edtFilter: TEdit;
procedure btnFilteredClick(Sender: TObject);
procedure FormCreate(Sender: TObject);
private
Filter: string;
FDMemTable: TFDMemTable;
procedure OnMyFilterRecord(DataSet: TDataSet; var Accept: Boolean);
public
{ Public declarations }
end; var
Form1: TForm1; implementation {$R *.dfm} procedure TForm1.OnMyFilterRecord(DataSet: TDataSet; var Accept: Boolean);
begin
Accept := Filter.IsEmpty or (DataSet.FieldByName('姓名').AsString = Filter);
end; procedure TForm1.btnFilteredClick(Sender: TObject);
begin
Filter := edtFilter.Text; FDMemTable.Filtered := False;
// 方法一
FDMemTable.Filter := '[姓名]=' + Filter.QuotedString;
FDMemTable.Filtered := True;
end; procedure TForm1.FormCreate(Sender: TObject);
begin
FDMemTable := TFDMemTable.Create(Self); with FDMemTable do
begin
with FieldDefs do
begin
Clear;
Add('姓名', ftWideString, );
Add('年龄', ftInteger);
end;
CreateDataSet;
AppendRecord(['张三', ]);
AppendRecord(['李四', ]);
AppendRecord(['王五', ]);
// 方法二
// OnFilterRecord := OnMyFilterRecord;
end;
ds1.DataSet := FDMemTable;
end; end.

FireDAC 中文字段过滤问题

由于开发工具都是洋大人的,对中文支持不是太友好,防止出现不可预料的BUG,建议尽量不要使用中文字段名。