knowrefcateda.cs

可以实现图书信息的管理笑话寻和山下湖

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.Text;
using System.Configuration;

/// <summary>
/// KnowRefCateDA 的摘要说明
/// </summary>
public class KnowRefCateDA
{
    private const string SQL_MAX_KNOWLEDGE_ID = "SELECT MAX(Knowledge_id)+1 FROM tb_Knowledge";
    private const string SQL_QUERY_CATEGORY_ID = "SELECT Category_id FROM tb_Category WHERE Category_name=@Category_name";
    private const string SQL_INSERT_REF_KNOW2CATE = "INSERT INTO tb_Ref_know2cate VALUES(@SQL_MAX_KNOWLEDGE_ID,@SQL_QUERY_CATEGORY_ID)";

    private const string PARAM_CATEGORY_NAME = "@Category_name";
    private const string PARAM_KNOWLEDGE_ID = "@Knowledge_id";
    private const string PARAM_CATEGORY_ID="@Category_id";


    public KnowRefCateDA()
	{
		//
		// TODO: 在此处添加构造函数逻辑
		//
	}


    public bool InsertRef_know2cate(KnowRefCateEntity know2cate)
    {
        StringBuilder strSQL = new StringBuilder();
        SqlParameter[] knowParams = GetParameters();
        SqlCommand cmd = new SqlCommand();

        // 依次给实体参数赋值
        knowParams[0].Value = know2cate.Knowledge_id;
        knowParams[1].Value = know2cate.Category_id;
       

        //遍历所有参数,并将参数添加到SqlCommand命令中
        foreach (SqlParameter parm in knowParams)
        {
            cmd.Parameters.Add(parm);
        }
        //取得数据库连接字符串
        using (SqlConnection conn = new SqlConnection(SqlHelper.ConnectionStringLocalTransaction))
        {
            //strSQL.Append(SQL_MAX_KNOWLEDGE_ID);
            //strSQL.Append(SQL_QUERY_CATEGORY_ID);
            strSQL.Append(SQL_INSERT_REF_KNOW2CATE);

            conn.Open();
            //设置Sqlcommand命令的属性
            cmd.Connection = conn;
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = strSQL.ToString();
            //执行添加的SqlCommand命令
            int val = cmd.ExecuteNonQuery();
            //清空SqlCommand命令中的参数
            cmd.Parameters.Clear();
            //判断是否添加成功，注意返回的是添加是否成功，不是影响的行数
            if (val > 0)
                return true;
            else
                return false;
        }
    }
    private static SqlParameter[] GetParameters()
    {
        //将SQL_INSERT_KNOWINFO做为哈希表缓存的键值
        SqlParameter[] parms = SqlHelper.GetCachedParameters(SQL_INSERT_REF_KNOW2CATE);

        //首先判断缓存是否已经存在
        if (parms == null)
        {
            //缓存不存在的情况下，新建参数列表
            parms = new SqlParameter[] {
                    new SqlParameter(PARAM_KNOWLEDGE_ID, SqlDbType.Int),
                    new SqlParameter(PARAM_CATEGORY_ID, SqlDbType.Int)};
                   


            //将新建的参数列表添加到哈希表中缓存起来
            SqlHelper.CacheParameters(SQL_INSERT_REF_KNOW2CATE, parms);
        }
        //返回参数数组
        return parms;
    }
}