ADO.NET 数据连接查询

static string  sqlcon = "server=.;database=;Integrated Security=true;";
/// <summary>
/// 新增数据
/// </summary>
public static void Add()
{
    //string sqlcon = "server=.;database=;Integrated Security=true;";
    SqlConnection conn=new SqlConnection(sqlcon);           
    string sqlStr="insert into Boook(b_id,b_title,b_author,b_money)values(1,'ASP.NET'，'莫言',100)";
    SqlCommand cmd=new SqlCommand(sqlStr,conn);
    conn.Open();
    int i = cmd.ExecuteNonQuery();
    conn.Close();
    if (i>0)
    {
        Console.Write("新增成功！");
    }
    else
    {
        Console.Write("新增失败！");
    }
}
/// <summary>
/// 删除数据
/// </summary>
public static void Delete()
{
    //string sqlcon = "server=.;database=;Integrated Security=true;";
    SqlConnection conn = new SqlConnection(sqlcon);
    string sqlStr = "delete from book where b_id=1";
    SqlCommand cmd = new SqlCommand(sqlStr,conn);
    conn.Open();
    int i = cmd.ExecuteNonQuery();
    conn.Close();
    if (i > 0)
    {
        Console.Write("删除成功！");
    }
    else
    {
        Console.Write("删除失败！");
    }
}
/// <summary>
/// 数据更新，软删除
/// </summary>
private static void Update()
{
    //string sqlcon = "server=.;database=;Integrated Security=true;";
    SqlConnection conn = new SqlConnection(sqlcon);
    string sqlStr = "update Boook set b_id =2 where b_id=1";
    SqlCommand cmd = new SqlCommand(sqlStr, conn);
    conn.Open();
    int i = cmd.ExecuteNonQuery();
    conn.Close();
    if (i > 0)
    {
        Console.Write("更新成功！");
    }
    else
    {
        Console.Write("更新失败！");
    }
}
/// <summary>
/// 读取单个值
/// </summary>
private static void selectSingle()
{
    SqlConnection conn = new SqlConnection(sqlcon);
    string sqlStr = "select * from Book";
    SqlCommand cmd = new SqlCommand(sqlStr, conn);
    conn.Open();
    object obj = cmd.ExecuteScalar();
    conn.Close();
    Console.Write(obj.ToString());
}
/// <summary>
/// dateReader读取数据，逐行读取，通过下表访问列
/// </summary>
private static void dateReader()
{
    SqlConnection conn = new SqlConnection(sqlcon);
    string sqlStr = "select * from Book";
    SqlCommand cmd = new SqlCommand(sqlStr, conn);
    conn.Open();
    SqlDataReader dr = cmd.ExecuteReader();
    if (dr.HasRows)
    {
        while (dr.Read())//如果读到下一行数据就返回True，且本身就属于那一行数据
        {
            Console.Write(dr[0].ToString() + '_' + dr[1].ToString()+'_'+dr["ID"].ToString());
        }
    }
    else
    {
        Console.Write("无数据");
    }
    dr.Close();
    conn.Close();
}

//使用适配器填充数据集  SqlDataAdapter不需要手动开关，它能够自己开关
public static void QueryListAdapter()
{
    SqlConnection con = new SqlConnection(sqlcon);
    string sqlStr = "select*from book";
    SqlDataAdapter da = new SqlDataAdapter(sqlStr,con);
    DataSet ds = new DataSet();
    da.Fill(ds);
    DataTable dt = ds.Tables[0];
    //循环数据表中的每一行
    for (int i = 0; i < dt.Rows.Count; i++)
    {
        DataRow dr = dt.Rows[i];//将表中的一行拿出来给行对象
        Console.WriteLine(dr[0].ToString() + "_" + dr["ID"].ToString());
    }
}

//使用适配器填充数据集  SqlDataAdapter不需要手动开关，它能够自己开关
public static void QueryListAdapter2()
{
    SqlConnection con = new SqlConnection(sqlcon);
    string sqlStr = "select*from book";
    SqlDataAdapter da = new SqlDataAdapter(sqlStr, con);
    DataSet ds = new DataSet();
    da.Fill(ds);
    DataTable dt = ds.Tables[0];
    //循环数据表中的每一行
    for (int i = 0; i < dt.Rows.Count; i++)
    {
        DataRow dr = dt.Rows[i];//将表中的一行拿出来给行对象
        Console.WriteLine(dr[0].ToString() + "_" + dr["ID"].ToString());
    }
}
//调用存储过程查询数据
public static void QuerListByProc()
{
    SqlConnection conn = new SqlConnection(sqlcon);
    SqlCommand cmd=new SqlCommand("usp_GetBookMyCateId",conn);
    //无参数的存储过程
    SqlParameter sp2 = new SqlParameter();
    sp2.ParameterName = "@cateId";
    sp2.SqlDbType = SqlDbType.Int;
    sp2.Value = 2;
    cmd.Parameters.Add(sp2);
    //有两个参数的存储过程
    SqlParameter sp = new SqlParameter("@cateId", 2);
    cmd.Parameters.Add(sp);
    SqlDataAdapter da = new SqlDataAdapter();
    DataTable dt = new DataTable();
    da.Fill(dt);
    foreach(DataRow dr in dt.Rows)
    {
        Console.WriteLine(dr[0].ToString() + "_" + dr["ID"].ToString());
    }
}
//调用多个参数的存储过程查询
private static void QueryListByProc2()
{
    SqlConnection conn = new SqlConnection(sqlcon);
    SqlCommand cmd = new SqlCommand("proGetPageData", conn);
    cmd.CommandType = CommandType.StoredProcedure;
    //尽量不要使用两个参数的存储过程，类型是枚举类型，另外一个两个参数的函数值混淆
    //SqlParameter par = new SqlParameter("@Id", DbType.Int32);
    //SqlParameter par = new SqlParameter("@id", 11);
    //赋值多个参数
    SqlParameter[] paras ={
                             new SqlParameter("@pageIndex",SqlDbType.Int,4),//这里的4是代表整型的长度
                             new SqlParameter("@pageSize",SqlDbType.Int,4)
                         };
    //cmd.Parameters.AddRange(paras);
    paras[0].Value = 1;//搜索第一页
    paras[1].Value = 2;//赋值的
    cmd.Parameters.AddRange(paras);//为command对象添加pameters数组
    conn.Open();
    //SqlDataReader dr = cmd.ExecuteReader();
    //while (dr.Read())
    //{
    //    Console.Write("id=" + dr[0].ToString());
    //}
    //dr.Close();
    SqlDataAdapter da = new SqlDataAdapter(cmd);
    DataTable dt = new DataTable();
    da.Fill(dt);
    foreach (DataRow dr in dt.Rows)
    {
        Console.WriteLine(dr[0].ToString() + "_" + dr[1].ToString());
    }
    conn.Close();
}

//调用带输出参数的存数过程
private static void QuerListProc3()
{
    SqlConnection conn = new SqlConnection(sqlcon);
    SqlCommand cmd = new SqlCommand("proGetData2", conn);
    SqlParameter[] paras ={
                             new SqlParameter("@pageIndex",SqlDbType.Int),
                             new SqlParameter("@pageSize",SqlDbType.Int),
                             new SqlParameter("@pageCount",SqlDbType.Int),
                             new SqlParameter("@rowCount",SqlDbType.Int)   
                         };
    paras[0].Value = 1;
    paras[1].Value = 2;
    paras[2].Direction = ParameterDirection.Output;
    paras[3].Direction = ParameterDirection.Output;//设置参数的输出方向
    cmd.Parameters.AddRange(paras);
    SqlDataAdapter da = new SqlDataAdapter(cmd);
    DataTable dt = new DataTable();
    da.Fill(dt);
    foreach (DataRow dr in dt.Rows)
    {
        Console.WriteLine(dr[0].ToString() + "_" + dr[1].ToString());
    }
    int pageCount=Convert.ToInt32(cmd.Parameters[2].Value);
    int rowCount=Convert.ToInt32(cmd.Parameters[3].Value);//获取输出参数
    Console.WriteLine("pageCount=" + pageCount + ",rowCount=" + rowCount);
}