我想将
linq查询结果转换为datatable,以便我可以将数据表分配给GridView以在asp页面上显示它.
但是我无法将结果转换为datatable,我没有在我的代码中获取CopyToTable()方法.
请告诉我这里做错了什么？
var gradeData = (from data in oAngieCtxt.prc_ShopInstanceCustomersData(Convert.ToInt32(this.ShopInstanceID),10000,false)
.Where( row => row.RecievedPoints != "n/a" )
.GroupBy(row => new { row.Name })
.Select(g => new GroupedPoints()
{
Name = g.Key.Name,TotalPoints = g.Sum(x => Convert.ToDouble(x.RecievedPoints) * (x.Weightage.ToString() == "0.00" ? 1 : Convert.ToDouble(x.Weightage)))
})
select data).ToList();
DataTable dt = gradeData --gradeData.CopyToTable()
注意：可以使用对dataextentions dll的引用.
提前致谢
解决方法
你应该得到
DataTableExtensions.CopyToDataTable
删除ToList().
CopyToDataTable是IEnumerable< DataRow>延期(不幸的是).
下面有一个自定义CopyToDataTable扩展方法的解决方案.
var gradeData = (from data in oAngieCtxt.prc_ShopInstanceCustomersData(
Convert.ToInt32(this.ShopInstanceID),false)
.Where( row => row.RecievedPoints != "n/a" )
.GroupBy(row => new { row.Name })
.Select(g => new
{
Name = g.Key.Name,TotalPoints = g.Sum(x => Convert.ToDouble(x.RecievedPoints)
* (x.Weightage.ToString() == "0.00" ? 1
: Convert.ToDouble(x.Weightage)))
})
select data);
var dt = gradeData.CopyToDataTable();
编辑：
这是CopyToDataTable的更有用的实现DataRow没有类型约束.
public static class DataSetLinqOperators
{
public static DataTable CopyToDataTable<T>(this IEnumerable<T> source)
{
//you find the ObjectShredder implementation on the blog wich was linked.
return new ObjectShredder<T>().Shred(source,null,null);
}
public static DataTable CopyToDataTable<T>(this IEnumerable<T> source,DataTable table,LoadOption? options)
{
return new ObjectShredder<T>().Shred(source,table,options);
}
}
