从数据库中读数据中寻找若隐若现的OOP

最近因为一直在看ext
所以和json 打交道打的比较多，
以前都是习惯性的
把数据读到dataset
之后调用ConvertToJson方法
(博客园有这个，只不过与ext的json稍微有点bug，更正在下面)

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.Text;
using System.Collections;
using System.Globalization;
using System.Reflection;

/**//// <summary>
/// ConvertToJson一个存储对象，收获Json
/// </summary>

//非著乃编。。。。 

 
public class JsonConvert
{
    private static void WriteDataRow(StringBuilder sb, DataRow row)
    {
        sb.Append("{");
        foreach (DataColumn column in row.Table.Columns)
        {
            sb.AppendFormat("\"{0}\":", column.ColumnName);
            WriteValue(sb, row[column]);
            sb.Append(",");
        }
        // Remove the trailing comma.
        if (row.Table.Columns.Count > 0)
        {
            --sb.Length;
        }
        sb.Append("}");
    }

    private static void WriteDataSet(StringBuilder sb, DataSet ds)
    {
        sb.Append("{\"Tables\":{");
        foreach (DataTable table in ds.Tables)
        {
            sb.AppendFormat("\"{0}\":", table.TableName);
            WriteDataTable(sb, table);
            sb.Append(",");
        }
        // Remove the trailing comma.
        if (ds.Tables.Count > 0)
        {
            --sb.Length;
        }
        sb.Append("}}");
    }

    private static void WriteDataTable(StringBuilder sb, DataTable table)
    {
        sb.Append("{\"rows\":[");
        foreach (DataRow row in table.Rows)
        {
            WriteDataRow(sb, row);
            sb.Append(",");
        }
        // Remove the trailing comma.
        if (table.Rows.Count > 0)
        {
            --sb.Length;
        }
        sb.Append("]}");
    }

    private static void WriteEnumerable(StringBuilder sb, IEnumerable e)
    {
        bool hasItems = false;
        sb.Append("[");
        foreach (object val in e)
        {
            WriteValue(sb, val);
            sb.Append(",");
            hasItems = true;
        }
        // Remove the trailing comma.
        if (hasItems)
        {
            --sb.Length;
        }
        sb.Append("]");
    }

    private static void WriteHashtable(StringBuilder sb, Hashtable e)
    {
        bool hasItems = false;
        sb.Append("{");
        foreach (string key in e.Keys)
        {
            sb.AppendFormat("\"{0}\":", key.ToLower());
            WriteValue(sb, e[key]);
            sb.Append(",");
            hasItems = true;
        }
        // Remove the trailing comma.
        if (hasItems)
        {
            --sb.Length;
        }
        sb.Append("}");
    }

    private static void WriteObject(StringBuilder sb, object o)
    {
        MemberInfo[] members = o.GetType().GetMembers(BindingFlags.Instance | BindingFlags.Public);
        sb.Append("{");
        bool hasMembers = false;
        foreach (MemberInfo member in members)
        {
            bool hasValue = false;
            object val = null;
            if ((member.MemberType & MemberTypes.Field) == MemberTypes.Field)
            {
                FieldInfo field = (FieldInfo)member;
                val = field.GetValue(o);
                hasValue = true;
            }
            else if ((member.MemberType & MemberTypes.Property) == MemberTypes.Property)
            {
                PropertyInfo property = (PropertyInfo)member;
                if (property.CanRead && property.GetIndexParameters().Length == 0)
                {
                    val = property.GetValue(o, null);
                    hasValue = true;
                }
            }
            if (hasValue)
            {
                sb.Append("\"");
                sb.Append(member.Name);
                sb.Append("\":");
                WriteValue(sb, val);
                sb.Append(",");
                hasMembers = true;
            }
        }
        if (hasMembers)
        {
            --sb.Length;
        }
        sb.Append("}");
    }

    private static void WriteString(StringBuilder sb, string s)
    {
        sb.Append("\"");
        foreach (char c in s)
        {
            switch (c)
            {
                case '\"':
                    sb.Append("\\\"");
                    break;
                case '\\':
                    sb.Append("\\\\");
                    break;
                case '\b':
                    sb.Append("\\b");
                    break;
                case '\f':
                    sb.Append("\\f");
                    break;
                case '\n':
                    sb.Append("\\n");
                    break;
                case '\r':
                    sb.Append("\\r");
                    break;
                case '\t':
                    sb.Append("\\t");
                    break;
                default:
                    int i = (int)c;
                    if (i < 32 || i > 127)
                    {
                        sb.AppendFormat("\\u{0:X04}", i);
                    }
                    else
                    {
                        sb.Append(c);
                    }
                    break;
            }
        }
        sb.Append("\"");
    }
    public static void WriteValue(StringBuilder sb, object val)
    {
        if (val == null || val == System.DBNull.Value)
        {
            sb.Append("null");
        }
        else if (val is string || val is Guid)
        {
            WriteString(sb, val.ToString());
        }
        else if (val is bool)
        {
            sb.Append(val.ToString().ToLower());
        }
        else if (val is double ||
            val is float ||
            val is long ||
            val is int ||
            val is short ||
            val is byte ||
            val is decimal)
        {
            sb.AppendFormat(CultureInfo.InvariantCulture.NumberFormat, "{0}", val);
        }
        else if (val.GetType().IsEnum)
        {
            sb.Append((int)val);
        }
        else if (val is DateTime)
        {
            sb.Append("new Date(\"");
            sb.Append(((DateTime)val).ToString("MMMM, d yyyy HH:mm:ss", new CultureInfo("en-US", false).DateTimeFormat));
            sb.Append("\")");
        }
        else if (val is DataSet)
        {
            WriteDataSet(sb, val as DataSet);
        }
        else if (val is DataTable)
        {
            WriteDataTable(sb, val as DataTable);
        }
        else if (val is DataRow)
        {
            WriteDataRow(sb, val as DataRow);
        }
        else if (val is Hashtable)
        {
            WriteHashtable(sb, val as Hashtable);
        }
        else if (val is IEnumerable)
        {
            WriteEnumerable(sb, val as IEnumerable);
        }
        else
        {
            WriteObject(sb, val);
        }
    }
    public static string ConvertToJson(object o)
    {
        StringBuilder sb = new StringBuilder();
        WriteValue(sb, o);
        return sb.ToString();
    }
}

随着项目的深入，
我发现这么做好处很显然，速度快，但是坏处也有，东西一多，到处都是dataset。。。
看了<你必须知道的.net >后，
我就在想，是不是我们需要把这些封装到类里面来传呢？

比如说表 
----------------------------------
table customers
----------------------------------
id                           int (PK)
name                      nvarchar(10)
sex                        bit
phone                    nvarchar(15)
Email                     nvarchar(30)
.                           .
.                           .
.                           .
----------------------------------
中，我先定义个类，基本情况如下


—————————————————
Student
—————————————————
+Id :int
+Name:string
+Sex:bool
+Phone:string
+Email:string
—————————————————
changeName(string):void
.
.
.
—————————————————
之后实例化它，先将表中的信息填写到这个对象里面
之后通过Json.Net 中的
string json = JavaScriptConvert.SerializeObject(student);
这样的话貌似每个都变成了对象方便处理,当然，也复杂不少。。。。

初学者，以往的blog 都不敢公开，
写到这个确实觉得确实有点意思，决定第一次放到新手区。。
希望得到各位高手指教，本人先在这里谢谢大家了。
code在下

using System;
using System.Data;
using System.Configuration;
using System.Collections;
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 Newtonsoft.Json;


public partial class Default2 : System.Web.UI.Page
{
    
    protected void Page_Load(object sender, EventArgs e)
    {
        //自己写的一个方法，实现的就是返回个dt,旧些时候的帖子上有这个的代码
        SqlCon sqlCon = new SqlCon("test1ConnectionString");
        DataTable dt = sqlCon.tableFromSql("select * from customers");
        // 返回dt完毕

        //看看dt中有多少行
        int count = dt.Rows.Count;

        //申明一个对象数组
        Customer[] customer = new Customer[count];
        
        //初始化每个对象
        for (int i = 0; i < count; i++)
        {
            customer[i] = new Customer();
            DataRow dr = dt.Rows[i];
            customer[i].Id = int.Parse(dr["id"].ToString());
            customer[i].Name = dr["Name"].ToString();
        }


        string a = JavaScriptConvert.SerializeObject(customer);
        Response.Write(a);
        /**//*result  here 
     
         * [
         * {"Id":1,"Name":"赵一","Sex":"Female","Email":null},
         * {"Id":2,"Name":"钱二","Sex":"Female","Email":null},
         * {"Id":3,"Name":"孙三","Sex":"Female","Email":null},
         * {"Id":4,"Name":"李四","Sex":"Female","Email":null}
         * ] 
         */

    }
}
class Customer
{
    private int _id;
    private string _name;
    private bool _sex;
    private string _email;
    public int Id
    {
        set {_id = value; }
        get { return _id; }
    }
    public string Name
    {
        set { _name = value.ToUpper(); }
        get { return _name; }
    }
    public string Sex
    {
        set 
        {
            if (value.ToUpper() == "True")
            {
                _sex = true;
            }
            else if (value.ToUpper() == "False")
            {
                _sex = false;
            }
            else
            {
                throw new Exception("input male or female only");
            }
        }
        get
        {
            if (_sex == true)
            { return "Male"; }
            else
            { return "Female"; }
        }
    }
    public string Email
    {    
        set 
        {
            if(Email.Contains("@")==false)
            {
                throw new Exception("input Wrong Email");
            }
            else
            {_email = value;}
        }
        get
        {
            return _email;
        }
       
    }
    public Customer()
    {
        //do Nothing
    }
    public Customer(int id,string name,string sex,string email)
    {
        this.Id = id;
        this.Name = name;
        this.Sex = sex;
        this.Email = email;
    }
    public void eating()
    {
        HttpContext.Current.Response.Write("cry"); 
    }
}