C SQLSERVER連線與使用

public

string
getconnectionstring
(string sqlname,
string basename,
string userid,
string password)
;initial catalog =;user id =;pwd ="
, sqlname, basename, userid, password);}
public
string
getconnectionstring
(string sqlname,
string basename,
bool security)
; initial catalog =; integrated security ="
, sqlname, basename, security);}
public
string
getconnectionstring
(string serverip,
int serverport,
string userid,
string password,
string basename)
;port=;user=;password=;database="
,serverip ,serverport,userid,password,basename)
;}

private

void
button2_click
(object sender,
eventargs e)
else
}catch
(exception
)}

方法使用情況

executenonquery

執行無返回內容的sql命令，create、insert、update、delete等

executescalar

執行返回第一行第一列的資料，其實也就是返回乙個值的命令，型別為object

endexecutereader

執行返回多行資料，select居多，返回型別是sqldatareader

executenonquery 用例；

private

void
button2_click
(object sender,
eventargs e)
catch
(exception
)}

try

catch
(exception
)

string str =

"data source=desktop-ckgfuub;initial catalog=client;user id = sa;pwd = herry084462"
;sqlconnection conn =
newsqlconnection
(str)
;            conn.
open()
;//string command = "insert into final values ('bi','女',24)";
string command =
"select * from final"
;sqlcommand sqlc =
newsqlcommand
(command, conn)
;sqldatareader reader = sqlc.
executereader()
;if(!reader.hasrows)
task.
run(()
=>}}
catch
(exception)}
);

// 查詢資料庫的所有表名

use mysoftware
select name from sysobjects where type=
'u'

create table student (

idint
identity(1
,1) primary key not null
,stuname nvarchar(10
),stu*** char(2
)null
,stuage int
null
)

insert into tablename values

(value1,value1,value1,value1)

update addressbook

set name=
'1'where name=
'2'

delete from

addressbook
where id=
10

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