我有几个方法返回不同的泛型列表。
在。net中存在任何类静态方法或将任何列表转换为数据表?我唯一能想到的是使用反射来做到这一点。
如果我有这个:
List<Whatever> whatever = new List<Whatever>();
(这下代码当然不工作,但我想有这样的可能性:
DataTable dt = (DataTable) whatever;
我有几个方法返回不同的泛型列表。
在。net中存在任何类静态方法或将任何列表转换为数据表?我唯一能想到的是使用反射来做到这一点。
如果我有这个:
List<Whatever> whatever = new List<Whatever>();
(这下代码当然不工作,但我想有这样的可能性:
DataTable dt = (DataTable) whatever;
当前回答
Dim counties As New List(Of County)
Dim dtCounties As DataTable
dtCounties = _combinedRefRepository.Get_Counties()
If dtCounties.Rows.Count <> 0 Then
For Each row As DataRow In dtCounties.Rows
Dim county As New County
county.CountyId = row.Item(0).ToString()
county.CountyName = row.Item(1).ToString().ToUpper()
counties.Add(county)
Next
dtCounties.Dispose()
End If
其他回答
我不得不修改Marc Gravell的示例代码来处理可空类型和空值。我在下面附上了一个工作版本。谢谢你马克。
public static DataTable ToDataTable<T>(this IList<T> data)
{
PropertyDescriptorCollection properties =
TypeDescriptor.GetProperties(typeof(T));
DataTable table = new DataTable();
foreach (PropertyDescriptor prop in properties)
table.Columns.Add(prop.Name, Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);
foreach (T item in data)
{
DataRow row = table.NewRow();
foreach (PropertyDescriptor prop in properties)
row[prop.Name] = prop.GetValue(item) ?? DBNull.Value;
table.Rows.Add(row);
}
return table;
}
MSDN上的这个链接值得一看:如何:实现CopyToDataTable<T>,其中泛型类型T不是一个数据流
这增加了一个扩展方法,让你这样做:
// Create a sequence.
Item[] items = new Item[]
{ new Book{Id = 1, Price = 13.50, Genre = "Comedy", Author = "Gustavo Achong"},
new Book{Id = 2, Price = 8.50, Genre = "Drama", Author = "Jessie Zeng"},
new Movie{Id = 1, Price = 22.99, Genre = "Comedy", Director = "Marissa Barnes"},
new Movie{Id = 1, Price = 13.40, Genre = "Action", Director = "Emmanuel Fernandez"}};
// Query for items with price greater than 9.99.
var query = from i in items
where i.Price > 9.99
orderby i.Price
select i;
// Load the query results into new DataTable.
DataTable table = query.CopyToDataTable();
Dim counties As New List(Of County)
Dim dtCounties As DataTable
dtCounties = _combinedRefRepository.Get_Counties()
If dtCounties.Rows.Count <> 0 Then
For Each row As DataRow In dtCounties.Rows
Dim county As New County
county.CountyId = row.Item(0).ToString()
county.CountyName = row.Item(1).ToString().ToUpper()
counties.Add(county)
Next
dtCounties.Dispose()
End If
您可以尝试以下内容
public static DataTable GetDataTableFromObjects(object[] objects)
{
if (objects != null && objects.Length > 0)
{
Type t = objects[0].GetType();
DataTable dt = new DataTable(t.Name);
foreach (PropertyInfo pi in t.GetProperties())
{
dt.Columns.Add(new DataColumn(pi.Name));
}
foreach (var o in objects)
{
DataRow dr = dt.NewRow();
foreach (DataColumn dc in dt.Columns)
{
dr[dc.ColumnName] = o.GetType().GetProperty(dc.ColumnName).GetValue(o, null);
}
dt.Rows.Add(dr);
}
return dt;
}
return null;
}
List<YourModel> data = new List<YourModel>();
DataTable dataTable = Newtonsoft.Json.JsonConvert.DeserializeObject<DataTable>(Newtonsoft.Json.JsonConvert.SerializeObject(data));