C# DataTable DataSet DataRow 转实体类集合，实体类和实体类集合转成DataTable 扩展方法分享
代码越写越灵活，分享越分享越快乐
public static class PropertiesExtension
{
public static string ToDescription(this PropertyInfo propertyInfo) {
var attr= propertyInfo.GetCustomAttribute<DescriptionAttribute>();
if (attr==null)
{
return propertyInfo.Name;
}
var description = attr.Description;
return description;
}
}
C# DataTable DataSet DataRow 转实体类集合，实体类和实体类集合转成DataTable 扩展方法分享
using System; using System.Collections.Generic; using System.Data; using System.Linq; using System.Reflection; namespace System { /// <summary> /// DataTable转list泛型集合 /// </summary> public static class DataTableExtend { /// <summary> /// DataTable转换List /// </summary> /// <typeparam name="T">泛型</typeparam> /// <param name="dt">DataTable</param> /// <returns>List泛型集合</returns> public static List<T> ToList<T>(this DataTable dt) where T : class, new() { var list = new List<T>(); foreach (DataRow dr in dt.Rows) { //泛型对象 T model = dr.ToDataRowModel<T>(); list.Add(model); } return list; } /// <summary> /// DataSet转换List /// </summary> /// <typeparam name="T">泛型</typeparam> /// <param name="dt">DataTable</param> /// <returns>List泛型集合</returns> public static List<T> ToList<T>(this DataSet ds) where T : class, new() { var list = new List<T>(); list = ds.Tables[0].ToList<T>(); return list; } /// <summary> /// DataRow转换T模型 /// </summary> /// <typeparam name="T">泛型</typeparam> /// <param name="dt">DataTable</param> /// <returns>List泛型集合</returns> public static T ToDataRowModel<T>(this DataRow dr) where T : class, new() { //泛型对象 T model = new T(); //属性集合 var listPro = model.GetType().GetProperties().Where(item => !item.IsDefined(typeof(InternalAttribute), false)).ToArray(); foreach (PropertyInfo pi in listPro) { var columnName = pi.Name;//属性=字段 var columnType = pi.PropertyType;//属性类型 var underlyingtype = Nullable.GetUnderlyingType(columnType);//返回指定可以为null值的类型 //判断属性是否可以写入 if (!pi.CanWrite) continue; if (!dr.Table.Columns.Contains(columnName)) continue; var value = dr[columnName]; //判断字段值是否为空 if (value == DBNull.Value) continue; //根据属性类型转换数据库字段类型 if (columnType == typeof(string)) pi.SetValue(model, value.ToString(), null); else if (columnType == typeof(int) || columnType == typeof(int?)) pi.SetValue(model, Convert.ToInt32(value), null); else if (columnType == typeof(DateTime) || columnType == typeof(DateTime?)) pi.SetValue(model, Convert.ToDateTime(value), null); else if (columnType == typeof(decimal)) pi.SetValue(model, Convert.ToDecimal(value), null); else if (columnType == typeof(double)) pi.SetValue(model, Convert.ToDouble(value), null); else if (columnType == typeof(float)) pi.SetValue(model, Convert.ToSingle(value), null); else if ((underlyingtype ?? columnType).IsEnum) { if (underlyingtype != null && !string.IsNullOrEmpty(value.ToString())) pi.SetValue(model, Enum.Parse(underlyingtype ?? columnType, value.ToString()), null); else if (underlyingtype == null && !string.IsNullOrEmpty(value.ToString())) pi.SetValue(model, Convert.ToInt32(value), null); else pi.SetValue(model, -1, null); } else pi.SetValue(model, value, null); } return model; } } }
实体列表转换成DataTable
/// <summary> /// 实体列表转换成DataTable /// </summary> /// <typeparam name="TEntity">实体</typeparam> /// <param name="entityList"> 实体列表</param> /// <returns></returns> public static DataTable EntityListToDataTable<TEntity>(this IList<TEntity> entityList) where TEntity : class { if (entityList == null) return null; var dt = new DataTable(typeof(TEntity).Name); var myPropertyInfo = typeof(TEntity).GetProperties(BindingFlags.Public | BindingFlags.Instance); #region 创建表结构 foreach (var property in myPropertyInfo) { Type colType = property.PropertyType; if (colType.IsGenericType && colType.GetGenericTypeDefinition() == typeof(Nullable<>)) { colType = colType.GetGenericArguments()[0]; var col = new DataColumn(property.Name, colType) { Caption = property.ToDescription() }; col.AllowDBNull = true; dt.Columns.Add(col); } else { var col = new DataColumn(property.Name, colType) { Caption = property.ToDescription() }; dt.Columns.Add(col); } } #endregion foreach (var entity in entityList) { if (entity == null) continue; var row = dt.NewRow(); foreach (var propertyInfo in myPropertyInfo) { if (propertyInfo.GetValue(entity, null) == null) row[propertyInfo.Name] = DBNull.Value; else row[propertyInfo.Name] = propertyInfo.GetValue(entity, null); } dt.Rows.Add(row); } return dt; }
实体转换成DataTable
/// <summary> /// 实体转换成DataTable /// Add by loki 20201011 /// </summary> /// <typeparam name="TEntity">实体</typeparam> /// <returns></returns> public static DataTable EntityToDataTable<TEntity>(this TEntity entity) where TEntity : class { if (entity == null) return null; var dt = new DataTable(typeof(TEntity).Name); var myPropertyInfo = typeof(TEntity).GetProperties(BindingFlags.Public | BindingFlags.Instance); #region 创建表结构 foreach (var property in myPropertyInfo) { Type colType = property.PropertyType; if (colType.IsGenericType && colType.GetGenericTypeDefinition() == typeof(Nullable<>)) { colType = colType.GetGenericArguments()[0]; var col = new DataColumn(property.Name, colType) { Caption = property.ToDescription() }; col.AllowDBNull = true; dt.Columns.Add(col); } else { var col = new DataColumn(property.Name, colType) { Caption = property.ToDescription() }; dt.Columns.Add(col); } } #endregion var row = dt.NewRow(); foreach (var propertyInfo in myPropertyInfo) { if (propertyInfo.GetValue(entity, null) == null) row[propertyInfo.Name] = DBNull.Value; else row[propertyInfo.Name] = propertyInfo.GetValue(entity, null); } dt.Rows.Add(row); return dt; }
你如果觉得有用就拿去不用谢！C# DataTable DataSet DataRow 转实体类集合，实体类和实体类集合转成DataTable 扩展方法分享，这里其实很简单，就是用到反射技术去实现的，将数据库表字段与C#实体属性进行反射
