C# 简单的连接数据库

[panyuan911]

C#中怎么使用数据库？
用本机SQL 自带的Northwind数据库执行 select count(*) from employees 就行
尽量简单一些

谢

[schoollong]

好多代码啊，呵呵
楼主有福了

[problem2050]

支持

[eagle_2008]

sqlConnection con = new sqlConnection("server=.;Integrated Secutity=true";database=Northwind;);
sqlAdapter adapter= new sqlAdapter("select count(*) from employees",con);
DataSet ds=new DataSet();
adapter.Fill(ds,"employees");
MessageBox.show(ds.Tables["employees"].Rows[0][0].ToString());

这个方法也可以

[hangang7403]

用SQL最好，不过也可以用OLEDBCONNECTION ，不过速度不如SQL快

[我姓区不姓区]

不要忘了using System.Data.SqlClient;

[panyuan911]

哈 多谢大家

[古龙老子]

[Quote=引用 1 楼 mylibin 的回复:]
C# code

using System.Data.SqlClient;
//.表示本地服务，也可以用127.0.0.1 代替//Northwind就是你的数据库名了
sqlConnection con = new sqlConnection("server=.;uid=sa;database=Northwind")
con.open();
sqlCommand cmd = new sqlCommand("select count(*) from employees",con)
sqlDataReader dr = cmd.ExecuteReader();
if(dr.Reader())
{
string count = dr[0].ToString();
}
con.close();
[/Quote]

[focuswe]

直接在web.config中配置或者
using System.Data.SqlClient;
//.表示本地服务，也可以用127.0.0.1 代替//Northwind就是你的数据库名了
sqlConnection con = new sqlConnection("server=.;uid=sa;database=Northwind")
con.open();
sqlCommand cmd = new sqlCommand("select count(*) from employees",con)
sqlDataReader dr = cmd.ExecuteReader();
if(dr.Reader())
{
string count = dr[0].ToString();
}
con.close();

[bestlove2008]

小弟想作个数状目录,想用鼠标右键点击某个节点的时候,能够弹出一个列表框,进行选择操作菜单:就像IIS,那样!

[weg910]

xuexi

[不慕沙卡拉卡]

楼上的已经说的很清楚了！
提一点 可以server=(local);表示本地服务器！

[wupiero]

[Quote=引用 1 楼 mylibin 的回复:]
C# code
sqlConnection con = new sqlConnection("server=.;uid=sa;database=Northwind")
con.open();
sqlCommand cmd = new sqlCommand("select count(*) from employees",con)
sqlDataReader dr = cmd.ExecuteReader();
if(dr.Reader())
{
string count = dr[0].ToString();
}
con.close();
[/Quote]

[liyin_liu]

jfjt

[gebz456]

都是引用的没意思

[还想懒够]

MSDN，搜ConnectionString就出来了

[exy337]

楼主偶的代码比较少,你看能帮到你吗.

using (SqlConnection conn = new SqlConnection("server=.;uid=sa;database=Northwind"))
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand("select count(*) from employees ", conn);
                int _count = (int)cmd.ExecuteScalar();
            }

[exy337]

[Quote=引用 24 楼 exy337 的回复:]
楼主偶的代码比较少,你看能帮到你吗.

using (SqlConnection conn = new SqlConnection("server=.;uid=sa;database=Northwind"))
{
conn.Open();
SqlCommand cmd = new SqlCommand("select count(*) from employees ", conn);
int _count = (int)cmd.ExecuteScalar();
}
[/Quote]
无须关闭,using中的内容自己关闭数据库的.相对来说会安全一点.

[exy337]

记得用
using System.Data.SqlClient;

[kingmax54212008]

using System.Data.SqlClient;
using (SqlConnection conn = new SqlConnection("server=.;uid=sa;database=Northwind"))
{
conn.Open();
SqlCommand cmd = new SqlCommand("select count(*) from employees ", conn);
int _count = (int)cmd.ExecuteScalar();
}

[龙宜坡]

[Quote=引用 1 楼 mylibin 的回复:]
C# code
sqlConnection con = new sqlConnection("server=.;uid=sa;database=Northwind")
con.open();
sqlCommand cmd = new sqlCommand("select count(*) from employees",con)
sqlDataReader dr = cmd.ExecuteReader();
if(dr.Reader())
{
string count = dr[0].ToString();
}
con.close();
[/Quote]