DataTable转换成List<T>

很多时候需要将DataTable转换成一组model，直接对model执行操作会更加方便直观。

代码如下：

 public static class DataTableToModel
    {
        public static List<T> ConvertToModel<T>(this DataTable dt)
        {
            if (dt == null || dt.Rows.Count == 0)
            {
                return null;
            }

            var result = new List<T>();

            var objType = typeof(T);
            var properties = objType.GetProperties();
            var columnNames = GetDataTableColumnNames(dt);

            foreach (DataRow dr in dt.Rows)
            {
                var obj = objType.Assembly.CreateInstance(objType.FullName);
                //var obj = Activator.CreateInstance(objType);
                foreach (var property in properties)
                {
                    if (columnNames.Contains(property.Name))
                    { 
                        var cellValue=dr[property.Name];
                        object propertyValue=cellValue;

                        //非泛型
                        if (!property.PropertyType.IsGenericType)
                        {
                            propertyValue = cellValue == null ? null : Convert.ChangeType(cellValue, property.PropertyType);
                        }
                        else //泛型Nullable<>
                        {
                            Type genericTypeDefinition = property.PropertyType.GetGenericTypeDefinition();
                            if (genericTypeDefinition == typeof(Nullable<>))
                            {
                                propertyValue = cellValue == null ? null : Convert.ChangeType(cellValue, Nullable.GetUnderlyingType(property.PropertyType));
                            }
                        }

                        property.SetValue(obj, propertyValue, null);
                    }
                }

                result.Add((T)obj);
            }

            return result;
        }

        private static HashSet<string> GetDataTableColumnNames(DataTable dt)
        {
            var columnNames = new HashSet<string>();
            foreach (DataColumn column in dt.Columns)
            {
                columnNames.Add(column.ColumnName);
            }
            return columnNames;
        }
    }