为何出错？(50分)

Z

zjmg

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GUEST, unregistred user!

• 2001-12-30

• #1

很菜的初级问题：为何将combobox1中选中的字段加入下列语句中报错?

procedure TForm2.Button1Click(Sender: TObject);
begin
Query1.close;
query1.sql.clear;
query1.sql.add('select 编号,性别,身高,出生年月');
query1.sql.add('from"hj.db"');
query1.sql.add('where 性别=combobox1.items[0]');
query1.prepare;
query1.open;
end;

 

R

rating

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GUEST, unregistred user!

• 2001-12-30

• #2

query1.sql.add('where 性别=combobox1.items[0]');
改为
query1.sql.add('where 性别=''combobox1.items[0]''');

 

鼠

鼠标

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GUEST, unregistred user!

• 2001-12-30

• #3

procedure TForm2.Button1Click(Sender: TObject);
begin
Query1.close;
query1.sql.clear;
query1.sql.add('select 编号,性别,身高,出生年月');
query1.sql.add('from hj');
query1.sql.add('where 性别= :性别');
query1.ParamByName('性别').Value := combobox1.items[0]');
query1.prepare;
query1.open;
end;

 

G

guyaling

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GUEST, unregistred user!

• 2001-12-30

• #4

同意楼上的

 

D

dongberlin

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GUEST, unregistred user!

• 2001-12-30

• #5

procedure TForm2.Button1Click(Sender: TObject);
begin
Query1.close;
query1.sql.clear;
query1.sql.add('select 编号,性别,身高,出生年月');
query1.sql.add('from"hj.db"');
query1.sql.add('where 性别='''+combobox1.items[0]+'''');
query1.prepare;
query1.open;
end;

 

S

SoftBoy

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2001-12-30

• #6

procedure TForm2.Button1Click(Sender: TObject);
begin
Query1.close;
query1.sql.clear;
query1.sql.add('select 编号,性别,身高,出生年月');
query1.sql.add(' from hj');
query1.sql.add(' where 性别='''+combobox1.items[0]+'''');
query1.prepare;
query1.open;
end;

 

C

cfx

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2001-12-30

• #7

softboy
说的对!

 

C

CJF

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GUEST, unregistred user!

• 2001-12-30

• #8

combobox1.items[0] －－－> combobox1.text

 

Y

ydl_2000

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GUEST, unregistred user!

• 2001-12-30

• #9

鼠标
说的都对！

 

I

iceheart

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2001-12-30

• #10

我一贯的写法是：
procedure TForm2.Button1Click(Sender: TObject);
var
sqltext:string；
begin
with query1 do
begin
sqltext:='select 编号,性别,身高,出生年月 from "bj.db" where 性别='''+combobox1.text+'''';
close;
sql.clear;
sql.add(sqltext);
prepare;
open;
end;
end;
這樣准沒問題。你就是錯在where後靣了。combobox.text是個字符串變量，
要讓sql語句明白，就要寫成我所寫的那個樣子。當然還有其它方法，如給
它一個參數之類，但都不如我寫的這個直觀且方便。

 

Z

zjmg

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2001-12-31

• #11

多人接受答案了。