通过反射填充泛型集合List的静态方法

呃```花了一晚上时间,终于搞出来了如何通过反射,从DataReader将数据填充到数据实体泛型集合的静态方法.

// Kchen.Core.BaseBusinessObject为通用数据实体类,此处仅为限定T所继承的类型
None.gif          public   static  IList < T >  FillDataListGeneric < T > (System.Data.IDataReader reader) where T : Kchen.Core.BaseBusinessObject
ExpandedBlockStart.gifContractedBlock.gif
         dot.gif {
InBlock.gif            
//实例化一个List<>泛型集合
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            IList<T> DataList = new List<T>();
InBlock.gif            
while (reader.Read())
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dot.gif{
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//由于是是未知的类型,所以必须通过Activator.CreateInstance()方法来依据T的类型动态创建数据实体对象
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                T RowInstance = Activator.CreateInstance<T>();
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//通过反射取得对象所有的Property
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                foreach (PropertyInfo Property in typeof(T).GetProperties())
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dot.gif{
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//BindingFieldAttribute为自定义的Attribute,用于与数据库字段进行绑定
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                    foreach (BindingFieldAttribute FieldAttr in Property.GetCustomAttributes(typeof(BindingFieldAttribute), true))
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dot.gif{
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try
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dot.gif{
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//取得当前数据库字段的顺序
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                            int Ordinal = reader.GetOrdinal(FieldAttr.FieldName);
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if (reader.GetValue(Ordinal) != DBNull.Value)
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dot.gif{
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//将DataReader读取出来的数据填充到对象实体的属性里
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                                Property.SetValue(RowInstance, Convert.ChangeType(reader.GetValue(Ordinal), Property.PropertyType), null);
ExpandedSubBlockEnd.gif                            }

ExpandedSubBlockEnd.gif                        }

InBlock.gif                        
catch
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dot.gif{
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break;
ExpandedSubBlockEnd.gif                        }

ExpandedSubBlockEnd.gif                    }

ExpandedSubBlockEnd.gif                }

InBlock.gif                
//将数据实体对象add到泛型集合中
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                DataList.Add(RowInstance);
ExpandedSubBlockEnd.gif            }

InBlock.gif            
return DataList;
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调用的时候使用如下代码

None.gif              // 伪代码 OleDbDataReader _ds = 创建一个OleDbDataReader 
None.gif
            IList < Product >  _result  =  Kchen.Utilities.FillDataListGeneric < Product > (_ds);


此静态方法通过一个实体类型和DateReader,快速的将数据填充到数据实体泛型集合中.

 

转载于:https://www.cnblogs.com/kchen/archive/2006/10/31/545011.html

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