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.Jet.OLEDB.4.0; 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 "{}"; } } }}

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