csharp:Conversion Between DataTable and List

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/// <summary>     /// http://www.codeproject.com/Tips/784090/Conversion-Between-DataTable-and-List-in-Csharp     /// </summary>     public static class ExtensionUtility     {               /// <summary>         /// Converts List To DataTable         /// </summary>         /// <typeparam name="TSource"></typeparam>         /// <param name="data"></param>         /// <returns></returns>         public static DataTable ToDataTable<TSource>(this IList<TSource> data)         {             DataTable dataTable = new DataTable(typeof(TSource).Name);             PropertyInfo[] props = typeof(TSource).GetProperties(BindingFlags.Public | BindingFlags.Instance);             foreach (PropertyInfo prop in props)             {                 dataTable.Columns.Add(prop.Name, Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);             }               foreach (TSource item in data)             {                 var values = new object[props.Length];                 for (int i = 0; i < props.Length; i++)                 {                     values[i] = props[i].GetValue(item, null);                 }                 dataTable.Rows.Add(values);             }             return dataTable;         }                   /// <summary>         /// Converts DataTable To List         /// </summary>         /// <typeparam name="TSource"></typeparam>         /// <param name="dataTable"></param>         /// <returns></returns>         public static List<TSource> ToList<TSource>(this DataTable dataTable) where TSource : new()         {             var dataList = new List<TSource>();               const BindingFlags flags = BindingFlags.Public | BindingFlags.Instance | BindingFlags.NonPublic;             var objFieldNames = (from PropertyInfo aProp in typeof(TSource).GetProperties(flags)                                  select new { Name = aProp.Name, Type = Nullable.GetUnderlyingType(aProp.PropertyType) ?? aProp.PropertyType }).ToList();             var dataTblFieldNames = (from DataColumn aHeader in dataTable.Columns                                      select new { Name = aHeader.ColumnName, Type = aHeader.DataType }).ToList();             var commonFields = objFieldNames.Intersect(dataTblFieldNames).ToList();               foreach (DataRow dataRow in dataTable.AsEnumerable().ToList())             {                 var aTSource = new TSource();                 foreach (var aField in commonFields)                 {                     PropertyInfo propertyInfos = aTSource.GetType().GetProperty(aField.Name);                     var value = (dataRow[aField.Name] == DBNull.Value) ? null : dataRow[aField.Name]; //if database field is nullable                     propertyInfos.SetValue(aTSource, value, null);                 }                 dataList.Add(aTSource);             }             return dataList;         }     }

　　测试数据源：

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public class Student     {         public long Id { get; set; }         public string Name { get; set; }         public short Age { get; set; }         public DateTime DateOfCreation { get; set; }         public bool? IsActive { get; set; }     }       public class Teacher     {         public long Id { get; set; }         public string Name { get; set; }         public Nullable<int> DepartmentId { get; set; }     }       public class Data     {         public static List<Student> GetStudents()         {             var list = new List<Student>             {                 new Student {Id = 1, Name = "Smith", Age = 18, DateOfCreation = DateTime.Now, IsActive = true},                 new Student {Id = 2, Name = "Hook", Age = 16, DateOfCreation = DateTime.Now.AddDays(-1), IsActive = true},                 new Student {Id = 3, Name = "Jhon", Age = 15, DateOfCreation = DateTime.Now.AddDays(-2), IsActive = true},                 new Student {Id = 4, Name = "Alan", Age = 21, DateOfCreation = DateTime.Now.AddDays(-3), IsActive = true}             };             return list;         }           public static List<Teacher> GetTeachers()         {             var list = new List<Teacher>             {                 new Teacher {Id = 1, Name = "Smith", DepartmentId = 18 },                 new Teacher {Id = 2, Name = "Hook", DepartmentId = 16 },                 new Teacher {Id = 3, Name = "Jhon", DepartmentId = 15 },                 new Teacher {Id = 4, Name = "Alan", DepartmentId = 21 }             };             return list;         }           public static DataTable DbNullInt()         {             DataTable table = new DataTable();             table.Columns.Add("Id", typeof(long));             table.Columns.Add("Name", typeof(string));               DataColumn column;             column = new DataColumn("DepartmentId", System.Type.GetType("System.Int32"));             column.AllowDBNull = true;             table.Columns.Add(column);               table.Rows.Add(1, "Smith", DBNull.Value);             table.Rows.Add(2, "Hook", 1);                 return table;         }     }

　　测试：

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List<Student> students = Data.GetStudents(); /*List to DataTable conversion*/ DataTable studentTbl = students.ToDataTable(); /*DataTable to List conversion*/ List<Student> newStudents = studentTbl.ToList<Student>();//ExtensionUtility.ToList<Student>(newStudents); this.dataGridView1.DataSource = newStudents;   /*List to DataTable conversion*/ DataTable teacherTbl = Data.DbNullInt(); /*DataTable to List conversion*/ List<Teacher> newTeachers = teacherTbl.ToList<Teacher>();     this.dataGridView2.DataSource = newTeachers;