ASP.NET中各种连接数据库的配置

一、数据库连接语句

1、MSSQL数据库链接示例

  <connectionStrings>
    <add name="Conn" connectionString="server=.;database=demo;uid=sa;pwd=123456" providerName="System.Data.SqlClient"/>
  </connectionStrings>

2、Access 2003数据库链接示例："{0}"代表根目录

  <connectionStrings>
    <add name="Conn" connectionString="Provider=Microsoft.Jet.OLEDB.4.0; Data Source={0}App_Data/demo.mdb" providerName="System.Data.OleDb"/>
  </connectionStrings>

Access 2007或以上版本的链接

  <connectionStrings>
    <add name="Conn" connectionString="Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0}App_Data/demo.mdb" providerName="System.Data.OleDb"/>
  </connectionStrings>

3、Oracle 数据库链接示例

 <connectionStrings>
    <add name="Conn" connectionString="Provider=MSDAORA;Data Source=demo;User ID=sa;Password=123456;" providerName="System.Data.OracleClient"/>
  </connectionStrings>

4、SQLite 数据库链接示例

 <connectionStrings>
    <add name="Conn" connectionString="Data Source={0}App_Data/demo.db;failifmissing=false" providerName="System.Data.SQLite"/>
  </connectionStrings>

5：MySQL数据库链接示例

  <connectionStrings>
    <add name="Conn" connectionString="host=127.0.0.1;Port=3306;Database=mysql;uid=sa;pwd=12346" providerName="MySql.Data.MySqlClient"/>
  </connectionStrings>

二、json数据转换

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Web;
using System.Web.Script.Serialization;

namespace Role.DAL
{
    public class Json
    {
        public Json() { }

        /// <summary>
        ///将datatable数据转换成JSON数据, 字符串拼接写成的
        /// </summary>
        /// <param name="jsonName">json名称。没发现什么作用</param>
        /// <param name="dt">得到的数据表</param>
        /// <returns></returns>
        public string DataTableToJson(string jsonName, DataTable dt)
        {
            StringBuilder Json = new StringBuilder();
            Json.Append("[");
            if (dt.Rows.Count > 0)
            {
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    Json.Append("{");
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        Json.Append(dt.Columns[j].ColumnName.ToString() + ":"" + dt.Rows[i][j].ToString() + """);
                        if (j < dt.Columns.Count - 1)
                        {
                            Json.Append(",");
                        }
                    }
                    Json.Append("}");
                    if (i < dt.Rows.Count - 1)
                    {
                        Json.Append(",");
                    }
                }
            }
            Json.Append("]");
            return Json.ToString();
        }


        /// <summary>
        /// 列表数据转换到json数据;字符串拼接写成的，太难
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="jsonName">json名称。没发现什么作用</param>
        /// <param name="IL"></param>
        /// <returns></returns>
        public string ObjectToJson<T>(string jsonName, IList<T> IL)
        {
            StringBuilder Json = new StringBuilder();
            Json.Append("[");
            if (IL.Count > 0)
            {
                for (int i = 0; i < IL.Count; i++)
                {
                    T obj = Activator.CreateInstance<T>();
                    Type type = obj.GetType();
                    PropertyInfo[] pis = type.GetProperties();
                    Json.Append("{");
                    for (int j = 0; j < pis.Length; j++)
                    {
                        Json.Append(pis[j].Name.ToString() + ":"" + pis[j].GetValue(IL[i], null) + """);
                        if (j < pis.Length - 1)
                        {
                            Json.Append(",");
                        }
                    }
                    Json.Append("}");
                    if (i < IL.Count - 1)
                    {
                        Json.Append(",");
                    }
                }
            }
            Json.Append("]");
            return Json.ToString();
        }

        /// <summary>
        /// 将DataTable转化为自定义JSON数据
        /// </summary>
        /// <param name="dt">数据表</param>
        /// <returns>JSON字符串</returns>   
        public static string DataTableToJson(DataTable dt)
        {
            StringBuilder JsonString = new StringBuilder();
            if (dt != null && dt.Rows.Count > 0)
            {
                List<Dictionary<string, string>> list = new List<Dictionary<string, string>>();
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    Dictionary<string, string> dict = new Dictionary<string, string>();
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        dict.Add(dt.Columns[j].ColumnName, dt.Rows[i][j].ToString());
                    }
                    list.Add(dict);
                }
                JavaScriptSerializer jsonSerializer = new JavaScriptSerializer();
                return jsonSerializer.Serialize(list);
            }
            else
            {
                return "{}";
            }
        }

        /// <summary>
        /// 将datatable转换为json  
        /// </summary>
        /// <param name="dtb">Dt</param>
        /// <returns>JSON字符串</returns>
        public static string Dtb2Json(DataTable dtb)
        {
            JavaScriptSerializer jss = new JavaScriptSerializer();
            System.Collections.ArrayList dic = new System.Collections.ArrayList();
            if (dtb != null && dtb.Rows.Count > 0)
            {
                foreach (DataRow dr in dtb.Rows)
                {
                    System.Collections.Generic.Dictionary<string, object> drow = new System.Collections.Generic.Dictionary<string, object>();
                    foreach (DataColumn dc in dtb.Columns)
                    {
                        drow.Add(dc.ColumnName, dr[dc.ColumnName]);
                    }
                    dic.Add(drow);
                }
                //序列化  
                return jss.Serialize(dic);
            }
            else
            {
                return "{}";
            }
        }

    }
}