C#读取对象实例的值和对对象的属性自动赋值方法
using System; using System.Data; using System.Reflection; namespace DBUtility { /// <summary> /// 对象实例操作辅助类 /// </summary> public static class InstanceHelper { /// <summary> /// 根据对象的属性名称,获取属性的值(用于根据对象自动完成参数化sql语句的赋值操作) /// </summary> /// <param name="propertyName">属性名称(忽略大小写)</param> /// <param name="objectInstance">对象实例</param> /// <param name="objectType">对象实例类型</param> /// <returns>属性的值</returns> public static object GetPropertyValue(string propertyName, object objectInstance, Type objectType) { PropertyInfo pi = objectType.GetProperty(propertyName, BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase); if (pi == null) throw new ArgumentException("自动设置参数值失败。参数化变量名称" + propertyName + "必须和对象中的属性名称一样。"); if (!pi.CanRead) throw new ArgumentException("自动设置参数值失败。对象的" + propertyName + "属性没有get方式,无法读取值。"); object value = pi.GetValue(objectInstance, null); if (value == null) value = DBNull.Value; else if (pi.PropertyType.Name == "DateTime" && Convert.ToDateTime(value) == DateTime.MinValue) value = DBNull.Value;//防止数据库是smalldatetime类型时DateTime.MinValue溢出 return value; } /// <summary> /// 将DataReader中的数据自动赋值到对象实例对应的属性 /// 注意:对象实例的属性名称必须和数据库列名相同,可忽略大小写 /// </summary> /// <param name="dataReader">SqlDataReader等数据阅读器获取的一行数据</param> /// <param name="objectInstance">对象实例</param> /// <param name="objectType">对象实例类型</param> public static void SetPropertyValue(IDataReader dataReader, object objectInstance, Type objectType) { for (int i = 0; i < dataReader.FieldCount; i++) { PropertyInfo pi = objectType.GetProperty(dataReader.GetName(i), BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase); if (pi != null && pi.CanWrite && dataReader[i] != DBNull.Value) { //如果是int?、bool?、double?等这种可空类型,获取其实际类型,如int?的实际类型是int Type baseType = Nullable.GetUnderlyingType(pi.PropertyType); if (baseType != null) pi.SetValue(objectInstance, Convert.ChangeType(dataReader[i], baseType), null); else pi.SetValue(objectInstance, Convert.ChangeType(dataReader[i], pi.PropertyType), null);//设置对象值 } } } #region 用于Oracle数据库操作 /// <summary> /// 根据对象的属性名称,获取属性的值(用于根据对象自动完成参数化sql语句的赋值操作) /// </summary> /// <param name="propertyName">属性名称(忽略大小写)</param> /// <param name="objectInstance">对象实例</param> /// <param name="objectType">对象实例类型</param> /// <returns>属性的值</returns> public static object GetPropertyValue2(string propertyName, object objectInstance, Type objectType) { PropertyInfo pi = objectType.GetProperty(propertyName, BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase); if (pi == null) throw new ArgumentException("自动设置参数值失败。参数化变量名称必须和对象中的属性名称一样。"); if (!pi.CanRead) throw new ArgumentException("自动设置参数值失败。对象的" + propertyName + "属性没有get方式,无法读取值。"); object value = pi.GetValue(objectInstance, null); if (value == null) value = DBNull.Value; else if (pi.PropertyType.Name == "DateTime" && Convert.ToDateTime(value) == DateTime.MinValue) value = DBNull.Value; else if (pi.PropertyType.Name == "Boolean")//oracle数据库用char(1)作为bool类型 value = OraBit(Convert.ToBoolean(value)); return value; } /// <summary> /// 将DataReader中的数据自动赋值到对象实例对应的属性 /// 注意:对象实例的属性名称必须和数据库列名相同,可忽略大小写 /// </summary> /// <param name="dataReader">OracleDataReader获取的一行数据</param> /// <param name="objectInstance">对象实例</param> /// <param name="objectType">对象实例类型</param> public static void SetPropertyValue2(IDataReader dataReader, object objectInstance, Type objectType) { for (int i = 0; i < dataReader.FieldCount; i++) { PropertyInfo pi = objectType.GetProperty(dataReader.GetName(i), BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase); if (pi != null && pi.CanWrite && dataReader[i] != DBNull.Value) { Type baseType = Nullable.GetUnderlyingType(pi.PropertyType);//获取其实际类型,如int?的实际类型是int if (baseType != null)//如果是int?、bool?、double?等可空类型 { if (baseType.Name == "Boolean") pi.SetValue(objectInstance, OraBool(dataReader[i].ToString()), null); else pi.SetValue(objectInstance, Convert.ChangeType(dataReader[i], baseType), null); } else { if (pi.PropertyType.Name == "Boolean") pi.SetValue(objectInstance, OraBool(dataReader[i].ToString()), null); else pi.SetValue(objectInstance, Convert.ChangeType(dataReader[i], pi.PropertyType), null);//设置对象值 } } } } /// <summary> /// Converter to use boolean data type with Oracle /// </summary> /// <param name="value">Value to convert</param> /// <returns></returns> public static string OraBit(bool value) { if (value) return "Y"; else return "N"; } /// <summary> /// Converter to use boolean data type with Oracle /// </summary> /// <param name="value">Value to convert</param> /// <returns></returns> public static bool OraBool(string value) { if (value.Equals("Y")) return true; else return false; } #endregion } }
posted on 2017-10-13 15:07 HOT SUMMER 阅读(2489) 评论(0) 编辑 收藏 举报