刚学用C#,看着资料连数据库就是连不上,我也不知道怎么回师,特那位大哥抽点时间给我讲解一下谢谢:
服务器名称:gis119
数据库名称:northwind
表名称:student(sno,sname,ssex,sage)
就拿这些给我讲下下面问题
1、如何连接数据库
2、随便说下插入、更新、查询
3、最好还有哪个DataReader最好是ASP。NET下的谢谢啊
谢谢啊
服务器名称:gis119
数据库名称:northwind
表名称:student(sno,sname,ssex,sage)
就拿这些给我讲下下面问题
1、如何连接数据库
2、随便说下插入、更新、查询
3、最好还有哪个DataReader最好是ASP。NET下的谢谢啊
谢谢啊
<add key="strConnection" value="Persist Security Info=False;User ID=sa;password=sa;Initial Catalog=northwind;Data Source=gis119"/>
<add key="ver" value="1.0.0 Build 20051029"/>
</appSettings>
查询数据库public DataView dataconn(string sql1)
{
try
{ DataSet DS1=new DataSet();
DS1.Clear();
SqlConnection myConnection = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["strConnection"].ToString());
Adapter1 = new SqlDataAdapter(sql1, myConnection);
Adapter1.Fill(DS1,"a");
return DS1.Tables["a"].DefaultView;
}
catch(Exception e)
{
return null;
} finally
{
myConnection.Close();
} }插入,修改,删除数据库public void update_Table(string sql)
{
try
{
SqlConnection myConnection = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["strConnection"].ToString());
myConnection.Open();
SqlCommand dataCommand = new SqlCommand(sql,myConnection);
dataCommand.ExecuteNonQuery();
}
catch(Exception e)
{
}
finally
{
myConnection.Close();
}
}关于datareader返回数据用逗号分割的字符串
public string getSBAllTree(string uid,string tablename)
{
int i=0;
string temp="";
string puid=uid;
string sql="select UID from "+tablename+" where PARENTID='"+puid+"' order by mc";
SqlCommand selcmd=new SqlCommand(sql, myConnection);
SqlDataReader myReader=selcmd.ExecuteReader();
while(myReader.Read())
{
string str=myReader.GetString(0);
treenode=treenode+"'"+str+"',";
i=i+1; }
myReader.Close();
if(treenode!=null)
{
return treenode.Substring(0,treenode.Length-1);
} }
string connString ="Server=gis119;Database=northwind;uid=sa;pwd=;"; SqlConnection conn = new SqlConnection(connString);
SqlDataAdapter da=new SqlDataAdapter(strSql,conn);
DataSet ds=new DataSet();
da.Fill(ds,"table");
conn.Open();
this.dataGrid1.DataSource = ds.Tables["table"];
this.dataGrid1.DataBindings();
conn.Close();