小白问题incompatible types

[zou_zq]

type
TArr = array of string;
Tbbzprintform = class(TForm)
DBGrid1: TDBGrid;
ComboBox1: TComboBox;
Button1: TButton;
Button2: TButton;
lfQuery: TADOQuery;
DataSource1: TDataSource;
procedure FormCreate(Sender: TObject);
procedure ComboBox1Change(Sender: TObject);
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
bbzprintform: Tbbzprintform;
// FieldName: String;

implementation
uses Unit6;

{$R *.dfm}

procedure Tbbzprintform.FormCreate(Sender: TObject);
begin
//ComboBox1.Text:='未打印';
ComboBox1.Items.Add('未打印');
ComboBox1.Items.Add('已打印');
ComboBox1.Items.Add('全部');
end;

procedure Tbbzprintform.ComboBox1Change(Sender: TObject);
begin

lfQuery.Close;
lfQuery.SQL.Clear;

if ComboBox1.Text='全部' then
Begin
lfQuery.SQL.Add('select * from driverinfo');
lfQuery.ExecSQL;
lfQuery.Open;

end

else
if ComboBox1.Text='未打印' then
Begin
lfQuery.SQL.Add('select * from driverinfo where d_print=:False');
lfQuery.ExecSQL;
lfQuery.Open;
end

else
if ComboBox1.Text='已打印' then
begin
lfQuery.SQL.Add('select * from driverinfo where d_print=:True');
lfQuery.ExecSQL;
lfQuery.Open;
end;

end;

procedure Tbbzprintform.Button1Click(Sender: TObject);

Var
j: Integer;
i: Integer;
arr:TArr;

begin
dbgrid1.datasource.dataset.Active:=True;
dbgrid1.datasource.dataset.first;
while not dbgrid1.datasource.dataset.eof do
begin
for j := 0 to dbgrid1.datasource.dataset.fieldcount -1 do
begin
arr[i][j] := dbgrid1.datasource.dataset.fields[j].asstring;//报错：incompatible types：'char' and 'string'
end;
dbgrid1.datasource.dataset.next;
end;
end;

end.

我是初学者，小白一个
把dbgrid里的值存到数组中

[bdmh]

没有给arr分配空间，而且arr也不是二维数组啊，瞎弄什么呢

[hongss]

arr:TArr;

看看你的Unit6里边有没有关于这个定义，是怎么定义的

[山东蓝鸟贵薪]

可能没有引用相关的单元

[sanguomi]

明显告诉你了， 类型不匹配

arr[i][j] := dbgrid1.datasource.dataset.fields[j].asstring;//报错：incompatible types：'char' and 'string'

arr[i][j] 是个字符串数组，再加个[j]就是字符了，再赋一个string，怎么能编译过

[zou_zq]

改了一下
type
TArr = array of array of string;//修改过的地方
Tbbzprintform = class(TForm)
DBGrid1: TDBGrid;
ComboBox1: TComboBox;
Button1: TButton;
Button2: TButton;
lfQuery: TADOQuery;
DataSource1: TDataSource;
procedure FormCreate(Sender: TObject);
procedure ComboBox1Change(Sender: TObject);
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
bbzprintform: Tbbzprintform;
// FieldName: String;

implementation
uses Unit6;

{$R *.dfm}

procedure Tbbzprintform.FormCreate(Sender: TObject);
begin
//ComboBox1.Text:='未打印';
ComboBox1.Items.Add('未打印');
ComboBox1.Items.Add('已打印');
ComboBox1.Items.Add('全部');
end;

procedure Tbbzprintform.ComboBox1Change(Sender: TObject);
begin

lfQuery.Close;
lfQuery.SQL.Clear;

if ComboBox1.Text='全部' then
Begin
lfQuery.SQL.Add('select * from driverinfo');
lfQuery.ExecSQL;
lfQuery.Open;

end

else
if ComboBox1.Text='未打印' then
Begin
lfQuery.SQL.Add('select * from driverinfo where d_print=:False');
lfQuery.ExecSQL;
lfQuery.Open;
end

else
if ComboBox1.Text='已打印' then
begin
lfQuery.SQL.Add('select * from driverinfo where d_print=:True');
lfQuery.ExecSQL;
lfQuery.Open;
end;

end;

procedure Tbbzprintform.Button1Click(Sender: TObject);

Var
j: Integer;
i: Integer;
arr:TArr;

begin
dbgrid1.datasource.dataset.Active:=True;
dbgrid1.datasource.dataset.first;
for i := 0 to dbgrid1.datasource.dataset.recordcount - 1 do //修改过的地方
begin
for j := 0 to dbgrid1.datasource.dataset.fieldcount -1 do
begin
arr[i][j] := dbgrid1.datasource.dataset.fields[j].asstring;//报错的地方
end;
dbgrid1.datasource.dataset.next;
end;
end;

end.

报错：数组没有初始化 variable 'arr'might not have been initialized
我刚接触delphi不到一个星期，别取笑我啊

[sanguomi]

要用 Setlength为 arr:TArr; 分配内存