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
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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
{ ///
/// DataTable转list泛型集合
///
public static class DataTableExtend
{ ///
/// DataTable转换List ///
/// 泛型
/// DataTable
/// List泛型集合
public static ListToList(this DataTable dt) where T : class, new()
{ var list = new List(); foreach (DataRow dr in dt.Rows)
{ //泛型对象
T model = dr.ToDataRowModel();
list.Add(model);
} return list;
} ///
/// DataSet转换List ///
/// 泛型
/// DataTable
/// List泛型集合
public static ListToList(this DataSet ds) where T : class, new()
{ var list = new List();
list = ds.Tables[0].ToList(); return list;
} ///
/// DataRow转换T模型 ///
/// 泛型
/// DataTable
/// List泛型集合
public static T ToDataRowModel(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
///
/// 实体列表转换成DataTable ///
/// 实体
/// 实体列表
///
public static DataTable EntityListToDataTable(this IList 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
///
/// 实体转换成DataTable /// Add by loki 20201011 ///
/// 实体
///
public static DataTable EntityToDataTable(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