picturedb.cs

ASP C#代码实例 适合初学人士学习使用

using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;

namespace Example_11_5
{
	/// <summary>
	/// Summary description for PictureDB.
	/// </summary>
	public class PictureDB
	{
		private readonly string SQLCONNECTIONSTRING = ConfigurationSettings.AppSettings["SQLCONNECTIONSTRING"].ToString();

		public int AddPicture(String sPictureDesn,byte[] bPictureData,String sPictureType)
		{
			//定义数据库的Connection and Command 
			SqlConnection myConnection = new SqlConnection(SQLCONNECTIONSTRING);
			SqlCommand myCommand = new SqlCommand("Pr_AddPicture",myConnection);

			//定义访问数据库的方式为存储过程
			myCommand.CommandType = CommandType.StoredProcedure;

			//创建访问数据库的参数	
			SqlParameter parameterPictureDesn = new SqlParameter("@PictureDesn",SqlDbType.VarChar,50);
			parameterPictureDesn.Value = sPictureDesn;
			myCommand.Parameters.Add(parameterPictureDesn);

			SqlParameter parameterPictureData = new SqlParameter("@PictureData",SqlDbType.Image);
			parameterPictureData.Value = bPictureData;
			myCommand.Parameters.Add(parameterPictureData);

			SqlParameter parameterPictureType = new SqlParameter("@PictureType",SqlDbType.VarChar,50);
			parameterPictureType.Value = sPictureType;
			myCommand.Parameters.Add(parameterPictureType);

			SqlParameter parameterPictureID = new SqlParameter("@PictureID",SqlDbType.Int,4);
			parameterPictureID.Direction = ParameterDirection.ReturnValue;
			myCommand.Parameters.Add(parameterPictureID);

			try
			{
				//打开数据库的连接
				myConnection.Open();
			}
			catch(Exception ex)
			{
				throw new Exception("数据库连接失败!",ex);
			}

			try 
			{
				//执行数据库的存储过程（访问数据库）
				myCommand.ExecuteNonQuery();
			}
			catch(Exception ex)
			{
				throw new Exception(ex.Message,ex);
			}
			finally 
			{
				if (myConnection.State == ConnectionState.Open)
				{
					//关闭数据库的连接
					myConnection.Close();
				}
			}

			return (int)parameterPictureID.Value;
		}

		public SqlDataReader GetSinglePicture(int nPictureID)
		{
			//定义数据库的Connection and Command 
			SqlConnection myConnection = new SqlConnection(SQLCONNECTIONSTRING);
			SqlCommand myCommand = new SqlCommand("Pr_GetSinglePicture",myConnection);

			//定义访问数据库的方式为存储过程
			myCommand.CommandType = CommandType.StoredProcedure;

			//添加储存过程的参数
			SqlParameter parameterPictureID = new SqlParameter("@PictureID",SqlDbType.Int,4);
			parameterPictureID.Value = nPictureID;
			myCommand.Parameters.Add(parameterPictureID);

			SqlDataReader dr = null;

			try
			{
				//打开数据库的连接
				myConnection.Open();
			}
			catch(Exception ex)
			{
				throw new Exception("数据库连接失败!",ex);
			}

			try
			{
				//执行数据库的存储过程（访问数据库）
				dr = myCommand.ExecuteReader(CommandBehavior.CloseConnection);
			}
			catch(Exception ex)
			{
				throw new Exception(ex.Message,ex);
			}

			//返回 dr
			return dr;
		}
	}
}