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Remove rows and adjust number

I am trying to remove objects from a list where a certain property value are identical to the previous/next objects property value. If an object are found I need to update the nested objects value.
Example:
Level | Text
1 | General
2 | Equipment
3 | Field Staff
2 | Scheduling
3 | Scheduling
4 | Deadlines
4 | Windows
1 | Specialities
In the example above I want to remove the second Scheduling and change the Deadlines Level to 3 as well as the Windows to 3.
I tried to look a head and compare with the next object in the list and also keep a counter but it didnt work.
int counter = 0;
for (int i = 0; i < notes.Count(); i++)
{
if (i <= notes.Count() - 1)
{
var currentRow = notes.ElementAt(i);
var nextRow = notes.ElementAt(i + 1);
if (currentRow.Text.Equals(nextRow.Text))
{
notes.Remove(nextRow);
counter++;
}
else
{
notes.ElementAt(i).Level = notes.ElementAt(i).Level - counter;
counter = 0;
}
}
}
Could anyone point me in the correct direction?

You can do it with Linq:
1 - Get distinct lines
var distinctList = notes
.GroupBy(p => p.Text)
.Select(v => v.First());
2 - get deleted level
IEnumerable<int> deletedLevel = notes
.Except(distinctList)
.Select(l => l.Level);
3 - update your distinct list
foreach(int level in deletedLevel)
{
distinctList
.Where(l => l.Level >= level + 1)
.ToList()
.ForEach(item => { item.Level -= 1; });
}
Result :
Level | Text
1 | General
2 | Equipment
3 | Field Staff
2 | Scheduling
3 | Deadlines
3 | Windows
1 | Specialities
i hope that will help you out

Try this:
var query = notesList.GroupBy(x => x.Text)
.Where(g => g.Count() > 1)
.Select(y => y.Key)
.Select(y => new { Element = y, Index = Array.FindIndex<Notes>(notesList.ToArray(), t => t.Text ==y) })
.ToList();
var filteredList = new List<Notes>();
foreach (var duplicate in query)
{
filteredList = notesList.Where((n, index) => index < duplicate.Index + 1).ToList();
var newElems = notesList.Where((n, index) => index > duplicate.Index + 1).Select(t =>
new Notes {Level = t.Level == 1 ? 1 : t.Level - 1, Text = t.Text});
filteredList.AddRange(newElems);
}

Delete duplicates within a single collection c#

I'm new to C#, here is my problem
My expected result is removing the entire row of ABC.
Both rows (with duplicate ABC) will be removed.
I need to do it the iterative way. Can't use distinct and stuff as recommended by the other post.
I tried to remove duplicates but it didn't work.
So i decided to add the non-duplicates to a new collection.
But it isn't working as well.
CollectionIn --> My sample collection
| Folder| Times
------------------------
| ABC | 3 |
| CDE | 2 |
| ACD | 2 |
| ABC | 1 |
CollectionOut = new DataTable();
CollectionOut.Columns.Add("Folder");
CollectionOut.Columns.Add("Times");
bool duplicate = false;
for (int i = 0; i < CollectionIn.Rows.Count; i++)
{
string value1 = CollectionIn.Rows[i].ItemArray[0].ToString().ToLower();
for (int z = 0; z < i; z++)
{
string value2 = CollectionIn.Rows[z].ItemArray[0].ToString().ToLower();
if (value1 == value2)
{
duplicate = true;
break;
}
}
if (!duplicate)
{
CollectionOut.Rows.Add(value1);
}
}
Can anyone help to take a look. Thanks!

Since you dont want to use Distinct, you cant do it with LINQ like:
var newList = myList.GroupBy(s=>s).Where(s => s.Count() == 1).ToList();

I would use Linq-To-DataTable:
List<DataRow> duplicates = CollectionIn.AsEnumerable()
.GroupBy(r => r.Field<string>("Folder"))
.Where(g => g.Count() > 1)
.SelectMany(grp => grp)
.ToList();
duplicates.ForEach(CollectionIn.Rows.Remove);
This will remove the duplicates from the original collection(DataTable) without creating a new.

How to compare 2 columns in different datatables

table1
id | fileName | fileDateTime
1 | somefile | somedatetime
2 | somefile2 | somedatetime2
table2
id | fileName | fileDateTime
| somefile1 | somedatetime1
| somefile2 | somedatetime2
output table3
id | fileName | fileDatetime
| somefile1 | somedatetime1
I want to compare the 2 tables (column 2 & 3 only) and only have what is not in both tables, there is no ID field in the 2nd table. Then I plan on parsing the data in the file and add file info to database to record file has been parsed. I am having trouble comparing the 2 fields. This does not seem to work.
for (int i = 0; i < finalTable.Rows.Count; i++)
{
for (int r = 0; r < filesTable.Rows.Count; i++)
{
if (finalTable.Rows[i][2] == filesTable.Rows[r][2])
{
finalTable.Rows.Remove(finalTable.Rows[i]);
}
}
}

Assuming the value is a string, you could just do
for (int i = 0; i < finalTable.Rows.Count; i++)
{
for (int r = 0; r < filesTable.Rows.Count; i++)
{
if (finalTable.Rows[r].Field<string>(2) == filesTable.Rows[r].Field<string>(2))
{
finalTable.Rows.Remove(finalTable.Rows[i]);
}
}
}
If it's another type, just change the <string> for the real type !

You can use Linq to achieve it as shown below.
Assuming your fields are string. For other datatype you can cast them accordingly:
using System.Data.Linq;
......
......
// Merge both tables data and group them by comparing columns values
dt1.Merge(dt2);
var g = dt1.AsEnumerable()
.GroupBy(x => x[0]?.ToString() + x[1]?.ToString()) // You can build Unique key here, I used string concatination
.ToDictionary(x => x.Key, y => y.ToList());
var unique = dt1.Clone();
foreach (var e in g)
{
if (e.Value.Count() == 1) // In either table - Intersaction
{
e.Value.CopyToDataTable(unique, LoadOption.OverwriteChanges);
}
if (e.Value.Count() == 2)
{
// In both tables -Union
}
}

How to add multi let operator and orderby in linq

I have more columns in datatable (about 100 columns). See examble below:
Column 1 | Column 2 | Column 3 | ..... | Column n
1;Nick | 1 | USA | ..... | Value 1
2;David | 2 | Reston | ..... | Value 2
3;Marry | 3 | Spain | ..... | Value 3
4;Join | 4 | Italy 3 | ..... Value 4
Dictionary<string, string > dict = new Dictionary<string, string>();
dict.Add("Column_1", "asc");
dict.Add("Column_2", "asc");
dict.Add("Column_1", "desc");
...................
dict.Add("Column_n", "asc");
var myRows = from row in datatable.AsEnumerable()
let myID = int.Parse(row.Field<string>("Column 2"))
let name = row.Field<string>("Column 1").Split(';')[1]
....
orderby myID ascending, name descending, ......, column n asc
select row;
My problem is how to loop all items in Dictionary to add more let statements and orderby all columns in Dictionary.
Please help me to fix it. My english is not good, sorry

Dictionary<string, string > dict = new Dictionary<string, string>();
dict.Add("col1", "ASC");
dict.Add("col2", "ASC");
dict.Add("col3", "DESC");
DataTable dt = new DataTable();
dt.Columns.Add("col1");
dt.Columns.Add("col2");
dt.Columns.Add("col3");
Random r = new Random();
for (int i = 0; i < 20; i++)
dt.Rows.Add(r.Next(10), r.Next(4), r.Next(2));
string sort = "";
foreach (KeyValuePair<string, string> entry in dict)
sort = sort + " " + entry.Key + " " + entry.Value + ",";
sort = sort.Substring(0, sort.Length - 1).Trim();
dt.DefaultView.Sort = sort;
dt = dt.DefaultView.ToTable();

Merging two datatable in memory and grouping them to get sum of columns.Using linq but kind of lost here

I have two table where two column are fixed. Some columns are identical and some are new.Columns are dynamic.
Have to do it in code level and I am trying to loop and conditions
What I want is to generate a report following the condition,
All columns in table1 and table2 must be present.
If a column is common and value is there it should be added with the identical row in other table.
If any row is present in one table but not in other, it should be included.
Example data
Table1
ID | NAME | P1 | P2 | P3
----------------------------
1 | A1 | 1 | 2 | 3.3
2 | A2 | 4.4 | 5 | 6
TABLE 2
ID | NAME | P1 | P2 | P4
---------------------------
1 | A1 | 10 | 11 | 12
2 | A2 | 12 | 14 | 15
3 | A3 | 16 | 17 | 18
Expected output:
ID | NAME | P1 | P2 | P3 | P4
---------------------------------
1 | A1 | 11 | 13 | 3.3 | 12
2 | A2 | 16.4 | 19 | 6 | 15
3 | A3 | 16 | 17 | null| 18
Progress till now:
First I merged those two table in to table1
table1.Merge(table2)
Then trying to group by over it
var query = from row in table1.AsEnumerable()
group row by new
{
ID = row.Field<int>("ID"),
Name = row.Field<string>("Name")
}
into grp
select new
{
ID = grp.Key.ID,
Name = grp.Key.Name,
Phase1 = grp.Sum(r => r.Field<decimal>("P1"))
};
I have modified this code to get a datatable. Please see attached cs file.
This is working, but as the number of columns are dynamic, I guess I have to repeat it for other columns and join all these small tables where one columns will be added.
How can I merge all those small tables?
I am lost here.Is there any other way. Its feeling as stupid thing.
Any help would be appreciated.
Attached File:
http://dl.dropbox.com/u/26252340/Program.cs

You want to use an implementation of a full outer join. Something like what follows.
Some setup so you can try this yourself:
DataTable t1 = new DataTable();
t1.Columns.Add("ID", typeof(int));
t1.Columns.Add("Name", typeof(string));
t1.Columns.Add("P1", typeof(double));
t1.Columns.Add("P2", typeof(double));
t1.Columns.Add("P3", typeof(double));
DataRow dr1 = t1.NewRow();
dr1["ID"] = 1;
dr1["Name"] = "A1";
dr1["P1"] = 1;
dr1["P2"] = 2;
dr1["P3"] = 3.3;
t1.Rows.Add(dr1);
DataRow dr2 = t1.NewRow();
dr2["ID"] = 2;
dr2["Name"] = "A2";
dr2["P1"] = 4.4;
dr2["P2"] = 5;
dr2["P3"] = 6;
t1.Rows.Add(dr2);
DataTable t2 = new DataTable();
t2.Columns.Add("ID", typeof(int));
t2.Columns.Add("Name", typeof(string));
t2.Columns.Add("P1", typeof(double));
t2.Columns.Add("P2", typeof(double));
t2.Columns.Add("P4", typeof(double));
DataRow dr3 = t2.NewRow();
dr3["ID"] = 1;
dr3["Name"] = "A1";
dr3["P1"] = 10;
dr3["P2"] = 11;
dr3["P4"] = 12;
t2.Rows.Add(dr3);
DataRow dr4 = t2.NewRow();
dr4["ID"] = 2;
dr4["Name"] = "A2";
dr4["P1"] = 12;
dr4["P2"] = 14;
dr4["P4"] = 15;
t2.Rows.Add(dr4);
DataRow dr5 = t2.NewRow();
dr5["ID"] = 3;
dr5["Name"] = "A3";
dr5["P1"] = 16;
dr5["P2"] = 17;
dr5["P4"] = 18;
t2.Rows.Add(dr5);
The queries look like:
var ids = (from r1 in t1.AsEnumerable() select new { ID = r1["ID"], Name = r1["Name"] }).Union(
from r2 in t2.AsEnumerable() select new { ID = r2["ID"], Name = r2["Name"] });
var query = from id in ids
join r1 in t1.AsEnumerable() on id equals new { ID = r1["ID"], Name = r1["Name"] } into left
from r1 in left.DefaultIfEmpty()
join r2 in t2.AsEnumerable() on id equals new { ID = r2["ID"], Name = r2["Name"] } into right
from r2 in right.DefaultIfEmpty()
select new
{
ID = (r1 == null) ? r2["ID"] : r1["ID"],
Name = (r1 == null) ? r2["Name"] : r1["Name"],
P1 = (r1 == null) ? r2["P1"] : (r2["P1"] == null) ? r1["P1"] : (double)r1["P1"] + (double)r2["P1"],
P2 = (r1 == null) ? r2["P2"] : (r2["P2"] == null) ? r1["P2"] : (double)r1["P2"] + (double)r2["P2"],
P3 = (r1 == null) ? null : r1["P3"],
P4 = (r2 == null) ? null : r2["P4"]
};

Got this solved by
table1.Merge(table2, true, MissingSchemaAction.Add);
finalTable = table1.Clone();
finalTable.PrimaryKey = new DataColumn[] { finalTable.Columns["ID"], finalTable.Columns["Name"] };
List<string> columnNames = new List<string>();
for (int colIndex = 2; colIndex < finalTable.Columns.Count; colIndex++)
{
columnNames.Add(finalTable.Columns[colIndex].ColumnName);
}
foreach (string cols in columnNames)
{
var temTable = new DataTable();
temTable.Columns.Add("ID", typeof(int));
temTable.Columns.Add("Name", typeof(string));
temTable.Columns.Add(cols, typeof(decimal));
(from row in table1.AsEnumerable()
group row by new { ID = row.Field<int>("ID"), Team = row.Field<string>("Team") } into grp
orderby grp.Key.ID
select new
{
ID = grp.Key.ID,
Name = grp.Key.Team,
cols = grp.Sum(r => r.Field<decimal?>(cols)),
})
.Aggregate(temTable, (dt, r) => { dt.Rows.Add(r.ID, r.Team, r.cols); return dt; });
finalTable.Merge(temTable, false, MissingSchemaAction.Ignore);
}

Since the columns are dynamic you'll need to return an object with dynamic properties. You could do this with an ExpandoObject.
The following code is ugly in many ways - I would do some massive refactoring before letting it go - but it gets the job done and might help you out to achieve what you want.
(Sorry for using the other linq syntax.)
var query = table1.AsEnumerable()
.GroupBy(row => new
{
ID = row.Field<int>("ID"),
Name = row.Field<string>("Name")
})
.Select(grp =>
{
dynamic result = new ExpandoObject();
var dict = result as IDictionary<string, object>;
result.ID = grp.Key.ID;
result.Name = grp.Key.Name;
foreach (DataRow row in grp)
{
foreach (DataColumn column in table1.Columns)
{
string columnName = column.ColumnName;
if (columnName.Equals("ID") || columnName.Equals("Name"))
continue;
//else
if (!dict.Keys.Contains(columnName))
dict[columnName] = row[columnName];
else
{
if (row[columnName] is System.DBNull)
continue;
if (dict[columnName] is System.DBNull)
{
dict[columnName] = row[columnName];
continue;
}
//else
dict[columnName] = (decimal)dict[columnName] + (decimal)row[columnName];
}
}
}
return result;
});