动态数据类型转换

using  System;
using  System.Collections.Generic;
using  System.Text;
using  System.Web.UI;
using  System.Reflection;
using  System.Web.UI.WebControls;

namespace  Toolkit
{
     ///   <summary>
     ///  表的字段设置/获到值操作类
     ///   </summary>
     public   class  TableValue
    {
        Object entity; // 实体对象
        Type typeInfo; // 实体对象类型
         ///   <summary>
         ///  表的字段设置/获到值操作类构造函数
         ///   </summary>
         ///   <param name="entityInstance"> 传进表的实体 </param>
         public  TableValue(Object entityInstance)
        {
            entity  =  entityInstance;
            typeInfo  =  entity.GetType();
        }
         ///   <summary>
         ///  将实体的值设置到控件中
         ///   </summary>
         ///   <param name="ct"></param>
         public   void  SetTo(Control ct)
        {
             string  propName  =  ct.ID.Substring( 3 );
             object  value  =  GetPropertyValue(propName);
             switch  (ct.GetType().Name)
            {
                 case   " TextBox " :
                    ((TextBox)ct).Text  =  Convert.ToString(value);
                     break ;
                 case   " Literal " :
                    ((Literal)ct).Text  =  Convert.ToString(value);
                     break ;
                 case   " Label " :
                    ((Label)ct).Text  =  Convert.ToString(value);
                     break ;
                 case   " DropDownList " :
                    ((DropDownList)ct).SelectedValue  =  Convert.ToString(value);
                     break ;
                 case   " CheckBox " :
                     bool  tempValue;
                     if  (Convert.ToString(value)  ==   " 1 " )
                    {
                        tempValue  =   true ;
                    }
                     else
                    {
                         bool .TryParse(Convert.ToString(value),  out  tempValue);
                    }
                    ((CheckBox)ct).Checked  =  tempValue;
                     break ;
            }
           
        }
         ///   <summary>
         ///  将控件的值设置到实体中[默认从控件中自动获取值]
         ///   </summary>
         ///   <param name="ct"> 控件 </param>
         ///   <param name="value"> 自定义值,若此值存在，则不从控件中获取值 </param>
         public   void  GetFrom(Control ct,  object  value)
        {
             string  propName  =  ct.ID.Substring( 3 );
             if  (value  ==   null )
            {
                 switch  (ct.GetType().Name)
                {
                     case   " TextBox " :
                        value  =  ((TextBox)ct).Text.Trim();
                         break ;
                     case   " Literal " :
                        value = ((Literal)ct).Text;
                         break ;
                     case   " Label " :
                        value  =  ((Label)ct).Text;
                         break ;
                     case   " DropDownList " :
                        value  =  ((DropDownList)ct).SelectedValue;
                         break ;
                     case   " CheckBox " :
                        value  =  ((CheckBox)ct).Checked;
                         break ;
                }
            }
            SetPropertyValue(propName, value);
        }
         ///   <summary>
         ///  将控件的值设置到实体中
         ///   </summary>
         ///   <param name="ct"> 控件 </param>
         public   void  GetFrom(Control ct)
        {
            GetFrom(ct,  null );
        }
         ///   <summary>
         ///  获取对象指定属性的值
         ///   </summary>
         ///   <param name="obj"> 对象 </param>
         ///   <param name="propName"> 属性名称 </param>
         ///   <returns></returns>
         private    object  GetPropertyValue( string  propName)
        {
            PropertyInfo prop  =  typeInfo.GetProperty(propName);
             return  prop.GetValue(entity,  null );
        }
         ///   <summary>
         ///  设置对象指定属性的值
         ///   </summary>
         ///   <param name="obj"> 对象 </param>
         ///   <param name="propName"> 属性名称 </param>
         ///   <returns></returns>
         private   void  SetPropertyValue( string  propName,  object  value)
        {
            PropertyInfo prop  =  typeInfo.GetProperty(propName);
            Type valueType  =   null ;
             if  (prop.PropertyType.Name.Contains( " Nullable " ))
            {
                valueType  =  Type.GetType(prop.PropertyType.FullName.Substring( 19 , prop.PropertyType.FullName.IndexOf( " , " )  -   19 ));
            }
             else
            {
                valueType  =  prop.PropertyType;
            }
             try
            {
                 if  (valueType.Name  !=   " DateTime "   ||  Convert.ToString(value)  !=   "" )
                {
                    value  =  System.ComponentModel.TypeDescriptor.GetConverter(valueType).ConvertFrom(Convert.ToString(value));
                    prop.SetValue(entity, value,  null );
                }
            }
             catch
            {
            }
        }
    }
}