zoukankan      html  css  js  c++  java
  • asp.net 常用数据库操作

        public SqlConnection conn = new SqlConnection(ConfigurationSettings.AppSettings["ConnStr"]);
        
    public SqlCommand cmd = new SqlCommand(); 
        
    public SqlDataAdapter objadpt = new SqlDataAdapter();
        
    public String sqlStr;
        DataTable dt 
    = new DataTable();   

        
    public basedata()
        {
            
    //
            
    // TODO: 在此处添加构造函数逻辑
            
    //
        }
        
    /// <summary>
        
    /// 根据sql语句返回查询结果
        
    /// </summary>
        
    /// <param name="sqlStr"></param>
        
    /// <returns></returns>
        public DataTable gettable(string sqlStr)
        {     
            
    if(conn .State== ConnectionState.Closed)
                conn.Open();
            cmd.Connection 
    = conn;
            cmd.CommandText 
    = sqlStr;
            objadpt.SelectCommand 
    = cmd;
        dt.Clear();
            objadpt.Fill(dt);
            
    if (conn.State == ConnectionState.Open)
               conn.Close();
            
    return dt;
        }

        
    /// <summary>
        
    /// 执行查询语句,返回SqlDataReader
        
    /// </summary>
        
    /// <param name="strSQL">查询语句</param>
        
    /// <returns>SqlDataReader</returns>
        public SqlDataReader GetReader(string sqlStr)
        {
            
    if (conn.State == ConnectionState.Closed)
                conn.Open();
            cmd.Connection 
    = conn;
            cmd.CommandText 
    = sqlStr;
            SqlDataReader myReader 
    = cmd.ExecuteReader();
            
    return myReader;
            
    if (conn.State == ConnectionState.Open)
                conn.Close();
        }

        
    /// <summary>
        
    /// 执行sql语句,如delete或update
        
    /// </summary>
        
    /// <param name="sqlStr"></param>
        public void executecmd(string sqlStr)
            {
            
    if (conn.State == ConnectionState.Closed)
                conn.Open();
            cmd.Connection 
    = conn;
            cmd.CommandText 
    = sqlStr;
             cmd.ExecuteNonQuery();
             
    if (conn.State == ConnectionState.Open)
                   conn.Close();
            }

        
    public string executecmdandback(string sqlStr)
        {
            
    string id;
            
    if (conn.State == ConnectionState.Closed)
                conn.Open();
            cmd.Connection 
    = conn;
            cmd.CommandText 
    = sqlStr + ";SELECT SCOPE_IDENTITY()";
            id 
    = cmd.ExecuteScalar().ToString();//添加配偶并返回刚添加的ID
            if (conn.State == ConnectionState.Open)
                conn.Close();
            
    return id;
        }
        
    /// <summary>
        
    /// 按条件返回查询结果
        
    /// </summary>
        
    /// <param name="sqlStr"></param>
        
    /// <returns></returns>
        public string getresult(string sqlStr)
            {
                
    string id;
            
    if (conn.State == ConnectionState.Closed)
                conn.Open();
            cmd.Connection 
    = conn;
            cmd.CommandText 
    = sqlStr;
            id 
    = Convert.ToString(cmd.ExecuteScalar());
            
    if (conn.State == ConnectionState.Open)
                conn.Close();
            
    return id;
    }
  • 相关阅读:
    Codeforces 1439B. Graph Subset Problem (思维,复杂度分析)
    石子游戏(nim游戏+按位考虑)
    Codeforces 1437F Emotional Fishermen(思维,dp)
    Codeforces Round #671 (Div. 2) (A~E)
    Java就业企业面试问题ssh框架
    DUBBO初探搭建DUBBO开发环境
    Spring容器组建注解@Component和Resouces实现完全注解配置
    jUnit 4 在 s2sh 中的应用
    4.5、常量、作用域、内置全局变量
    Java 诗词纵向转换字符流输出
  • 原文地址:https://www.cnblogs.com/ringwang/p/1447041.html
Copyright © 2011-2022 走看看