How to assign datatable value to a field in the list

prasanna p

6y1.1kLINQ

Hi friends, I am assigning values in the list { Name=item.field("name"), Date=dt.AsEnumerable() .where(y=>y.field("name")=field("name")) .Select(x=>x.field("date")).To list() } But the value is not assigning to the variable and showing system.datarowLinq...text in the output. I am getting cannot convert string[] to string I tried.ToString(),First() and firstorDefault() But I am unable to assign value Mar-2020 to the variable. How to get the correct value in the variable?

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Navaneeth Krishnan6y ago
https://forum.uipath.com/t/how-to-put-data-from-a-column-of-datatable-to-list-of-string/18409/3
Laxmidhar Sahoo6y ago
Hi Prasanna

It is correct .but what about dtresult variable .What is the data structure of this data table .

if the bellow query retuen multiple rows may cause error .

so call firstOrDefault().Tostring()

dttable.AsEnumerable()
.Where(row => row.Field("StudentName") == item.Field("name"))
.Select(s => s.Field("monthyear").FirstorDefault().tostring()

But it is not a correct way .The joining is the right path .
So please show the dtresult data structure

Thanks and regards
prasanna p6y ago
hi Laxmidhar Sahoo,

I created StudentStatus model in that LastOnline is a string field.So I need directly assing value to the LastOnline fileld in the list based on I am sending to the datatable.

It is in the list I am performing

List list = (from item in dtresult

select new StudentStatus

{

Id = item.Field("Id"),

Name = item.Field("name"),

LastOnline = dttable.AsEnumerable()

.Where(row => row.Field("StudentName") == item.Field("name"))

.Select(s => s.Field("monthyear")).ToList()

}).ToList();

It is inside the section.So how to do?
Laxmidhar Sahoo6y ago
hi

I am not aware about dtresult .if it is a data table then
var JoinResult = (from p in dtresult.AsEnumerable()
                          join t in dttable.AsEnumerable()
                          on p.Field<string>("name") equals t.Field<string>("StudentName")
                          select new
                          {
                              Id = p.Field<int>("Id"),
                              Name = p.Field<string>("name")

                          }).ToList();
Thanks and regards
prasanna p6y ago
Here is the code :

var dttable = ds.Tables[1].AsEnumerable();

Table Output:

StudentName monthyear

AAA              Mar-2020

BBB June-2020

cccc                 August-2020

List list =

(from item in dtresult

select new StudentStatus

{

Id = item.Field("Id"),

Name = item.Field("name"),

LastOnline = dttable.AsEnumerable()

.Where(row => row.Field("StudentName") == item.Field("name"))

.Select(s => s.Field("monthyear"))

.ToList(),

}).ToList();

I am getting the error to LastOnline field

Cannot implicitly convert type 'System.Collections.Generic.List' to string.

I want to display Mar-2020 in the Lastonline field based on  value coming in the item field.

Please tell me how to do this one.
Rajeesh Menoth6y ago
Hi,

Better to post complete code.

Please go through the following reference.

https://stackoverflow.com/questions/36043363/linq-where-condition-change-value-of-property