Question

asp.net (C#) 连接sql数据库后如何进行操作

这是我的连接代码不知道对不对？这是在cs文件中写的代码
using System.Data.SqlClient;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string strConnection = "user id=binbinceshi;password=binbinceshi;";
strConnection += "initial catalog=Northwind;Server=127.0.0.1;";
strConnection += "Connect Timeout=30";
SqlConnection objConnection = new SqlConnection(strConnection);
objConnection.Open();
SqlCommand com = new SqlCommand("selcet * from ceshi", objConnection);

}
}
到这里后再应该怎么操作才可以显示出里面的数据来，然后进行操作呢，希望各位高手能够指点，谢谢，如果您能帮我，可以与我联系，我QQ：350532994
我现在对于数据库已经晕了头了，所以大家在告诉小弟的时候，希望能写清楚点，谢谢各位兄弟姐妹了，谢谢

Answer 1

using System;
using System.Data;
using System.Data.SqlClient;
using System.Collections;

namespace M56kc_Forum
{
/// <summary>
/// DBOperate 的摘要说明。
/// </summary>
public class DBOperate
{
public DBOperate()
{
//
// TODO: 在此处添加构造函数逻辑
//
}

//输入SELECT语句，获得返回数据集
public static DataTable SelectFormForum(string sql,int start,int size,string tablename)
{
try
{
SqlConnection sqlConnection=new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["data"]);
SqlDataAdapter sqlAdapter1 = new SqlDataAdapter(sql, sqlConnection);
DataSet returns = new DataSet();
sqlAdapter1.Fill(returns,start,size,tablename);
return returns.Tables[0];
}
catch (Exception ex)
{
throw (ex);
}
}

public static DataTable SelectFormForum(string sql)
{
try
{
SqlConnection sqlConnection=new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["data"]);
SqlDataAdapter sqlAdapter1 = new SqlDataAdapter(sql, sqlConnection);
DataSet returns = new DataSet();
sqlAdapter1.Fill(returns);
return returns.Tables[0];
}
catch (Exception ex)
{
throw (ex);
}
}

//返回一条记录
public static DataRow GetDataRow(string sql,string TableName)
{
try
{
SqlConnection sqlConnection=new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["data"]);
SqlDataAdapter sqlAdapter1 = new SqlDataAdapter(sql, sqlConnection);
DataSet product = new DataSet();
sqlAdapter1.Fill(product, TableName);
return product.Tables[0].Rows[0];
}
catch (Exception ex)
{
throw (ex);
}
}

//执行SQL语句，如UPDATE，INSERT等
public static void ExcSQL(string s)
{
SqlConnection sqlConnection=new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["data"]);
try
{
SqlCommand sqlCmd =new SqlCommand(s,sqlConnection);
sqlConnection.Open();
sqlCmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw (ex);
}
finally
{
sqlConnection.Close();
}
}

//获取用户短消息条数
public static int ShortMsgCount(string UserName)
{
try
{
string s="SELECT COUNT(*) AS cun FROM ShortMessage WHERE (systemmsg = 0) AND (Readed = 0) AND (UserName = '"+UserName+"')";
DataRow dr=GetDataRow(s,"ShortMessage");
return System.Convert.ToInt32(dr["cun"].ToString());
}
catch
{
return 0;
}
}

//计算总共有多少条问题
public static int CalculateQRecord(int BID,int SID,int solved)
{
try
{
string s="SELECT COUNT(*) AS co FROM Questions WHERE (BigClass_ID = "+BID+") AND (SmallClass_ID = "+SID+") AND (kind > 0) AND (kind < 5) AND (solved = "+solved+")";
DataRow dr=GetDataRow(s,"Questions");
return System.Convert.ToInt32(dr["co"].ToString());
}
catch
{
return 0;
}
}

//计算总共有多少条回复
public static int CalculateARecord(int QID)
{
try
{
string s="SELECT COUNT(*) AS co FROM Answers WHERE (Question_ID = "+QID+")";
DataRow dr=GetDataRow(s,"Answers");
return System.Convert.ToInt32(dr["co"].ToString());
}
catch
{
return 0;
}
}

}
}

Answer 2

public DataSet GetConDB(string sql) { SqlConnection conn = new SqlConnection(); DataSet ds = new DataSet(); try { string strConnection = "user id=binbinceshi;password=binbinceshi;"; strConnection = "initial catalog=Northwind;Server=127.0.0.1;"; strConnection = "Connect Timeout=30"; conn = new SqlConnection(strConnection); conn.Open(); SqlDataAdapter sda = new SqlDataAdapter(sql, conn); sda.Fill(ds); return ds; } catch (Exception ex) { throw (ex); } finally { conn.Close(); } }

Answer 3

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
SqlConnection strConnection = new SqlConnection("uid=binbinceshi;pwd=binbinceshi;server=.;database=数据库名称");
DataSet ds = new DataSet();
SqlDataAdapter dap = new SqlDataAdapter("select * from 表名",strConnection);
dap.fill(ds);
this.DataGrid1.datasource = ds.table["表名"];
this.dataGrid1.databinder();

}
试试吧！！！