I have many checkbox lists for searching, but when I will search by any of the checkbox list search if any record will be two times in table means will not fill into gridview.
This line of code is not allowed duplicate values, if duplicate means allow single record.
if (newdt.TableName == dt.TableName) {
// see if filter is already present in the dataset
tableMatchFound = true;
// when the current filter is already present in the dataset
foreach (DataRow dr in dt.Rows)
ds.Tables[newdt.TableName].ImportRow(dr);
}
// importrow() adds distinct new subfilters to the existing filter, duplicate items are not added
if (!tableMatchFound)
ds.Tables.Add(dt);
Below is my full .cs code.
private DataTable list(String dbObject, String filterName, String filterValue,string PositonId,string Status) {
NameValuePairList objNameValuePairList = new NameValuePairList();
objNameValuePairList.Add(new NameValuePair("#FilterValue", filterValue, PositonId, Status));
objNameValuePairList.Add(new NameValuePair("#Action", "FilterBy" + filterName, PositonId, Status));
DataTable dt = dl.Search_RegisterationInfo(dbObject, objNameValuePairList, PositonId, Status);
return dt;
}
public DataTable list(String dbOject, FilterList myFilterList,string PositonId,string Status) {
// gets a collection(dataset) of all unique filters(datatables) and also group all subfilters(rows) under each filter
DataTable dt;
DataSet ds = new DataSet();
// a filter may be a Nationality or a Qualification
foreach (Filter item in myFilterList)
// a subfilter may be Indian or Expatriate under the filter Nationality
{
// another subfilter may be Bachelor degree or Master Degree under the filter Qualification
dt = list(dbOject, item.getFilterName, item.getFilterValue, PositonId,Status);
dt.TableName = item.getFilterName;
// datatables are named based on the filters
if (ds.Tables.Count == 0)
// so we get a collection of unique filters (datatables) in the dataset
ds.Tables.Add(dt);
// add new filter without checking, since for the first time, no conflicts are possible
else
{
bool tableMatchFound = false;
foreach (DataTable newdt in ds.Tables)
if (newdt.TableName == dt.TableName)
{
// see if filter is already present in the dataset
tableMatchFound = true;
// when the current filter is already present in the dataset
foreach (DataRow dr in dt.Rows)
ds.Tables[newdt.TableName].ImportRow(dr);
}
// importrow() adds distinct new subfilters to the existing filter, duplicate items are not added
if (!tableMatchFound)
ds.Tables.Add(dt);
}
// if the filter does not exist, add the new filter to the collection
}
// the entire collection of filters will contain duplicate items
// distinct items from the entire collection is filtered out in the next section
dt = ds.Tables[0].Clone();
// get the structure of the first filter as they all apply to the same table object
if (ds.Tables.Count == 1)
dt = ds.Tables[0];
// if there is only one filter, no filtering is required
else
// if there are more than one, compare each subfilter of every other filter with the subfilters of the first filter
foreach (DataRow dr in ds.Tables[0].Rows)
{
// each subfilter from the first filter is used as a pivot
int rowMatchFound = 1;
for (int i = 1; i < ds.Tables.Count; i++)
// search all filters except the first one
foreach (DataRow newdr in ds.Tables[i].Rows)
// select each subfilter from all the filter
if ((int)dr["RegistrationId"] == (int)newdr["RegistrationId"])
rowMatchFound++;
if (rowMatchFound == ds.Tables.Count)
// a match is found exactly once in all the filters
dt.ImportRow(dr);
// the final item is selected so that is is present in all the filters
}
return dt;
}
Please follow the link for more details of my question.
https://forums.asp.net/t/2078301.aspx?Duplicate+items+are+not+added+using+ASP+NET+C+
Related
The code below choose the first row and remove the other row below with specific id. The things that i want is the last line within the id.
var dtremove = RemoveDuplicateRows(dt, "id);
This the extension
public DataTable RemoveDuplicateRows(DataTable dt, string colName)
{
Hashtable hTable = new Hashtable();
ArrayList duplicateList = new ArrayList();
//Add list of all the unique item value to hashtable, which stores combination of key, value pair.
//And add duplicate item value in arraylist.
foreach (DataRow drow in dt.Rows)
{
if (hTable.Contains(drow[colName]))
{
duplicateList.Add(drow);
}
else
hTable.Add(drow[colName], string.Empty);
}
//duplicateList.Sort();
//Removing a list of duplicate items from datatable.
foreach (DataRow dRow in duplicateList)
dt.Rows.Remove(dRow);
//Datatable which contains unique records will be return as output.
return dt;
}
The example of datatable.
id date
------------
A 1/1/2018
A 1/2/2018
A 1/3/2018
B 2/1/2018
B 2/2/2018
i want the result like this.
id date
------------
A 1/3/2018
B 2/2/2018
I tried not to change too much of your code, pretty sure it can be improved, but the changes below looks for the value and if it already exists in the dictionary, it replaces it: Thus, you will end up with the very last row instead of the first one. Also, it returns a new DataTable and the original one will stay intact.
public DataTable RemoveDuplicateRows(DataTable dt, string colName)
{
var uniqueRows = new Dictionary<string, DataRow>();
foreach (DataRow thisRrow in dt.Rows)
{
if (uniqueRows.ContainsKey(colName))
{
uniqueRows[colName] = thisRrow;
}
else
{
uniqueRows.Add(colName, thisRrow);
}
}
DataTable copy = dt.Copy();
copy.Rows.Clear();
foreach (var thisRow in uniqueRows)
{
copy.Rows.Add(thisRow.Value);
}
//Datatable which contains unique records will be return as output.
return copy;
}
I have the following datagridview.
I need to filter and save rows separately that match Valid and Invalid property of the status column.
It do not have a datasource.So i'm creating a DataTable,filtering it and saving the results.But the filtering is not working as intended and contains results that does not match the expression
DataTable dt = new DataTable();
//Populating Virtual Table
foreach (DataGridViewColumn col in dataGridView4.Columns)
{
dt.Columns.Add(col.Name);
}
foreach (DataGridViewRow row in dataGridView4.Rows)
{
DataRow dRow = dt.NewRow();
foreach (DataGridViewCell cell in row.Cells)
{
dRow[cell.ColumnIndex] = cell.Value;
}
dt.Rows.Add(dRow);
}
Now creating a Filtered Table containing results where column named Status equals "Valid"
filtered = dt.Copy();
DataTable filteredResults = new DataTable();
DataTable filteredResults2 = new DataTable();
// filtered.Columns.Remove("Status");
var expression = string.Format("Status LIKE '%{0}%'", "Valid");
if (filtered.Select(expression).Any())
{
filteredResults = filtered.Select(expression).CopyToDataTable();
}
But the filtered data table contains elements which has the Status column value "Invalid".What i'm i doing wrong ? Please advice.
You are using LIKE in your expression. LIKE checks to see if the value contains the specified value. Use = instead.
I am trying to compare two datatables and capture the difference in third datatable.
DataTable one = new DataTable();
one.Columns.Add("ID");
one.Columns.Add("PCT");
one.Rows.Add("1", "0.1");
one.Rows.Add("2", "0.2");
one.Rows.Add("3", "0.3");
DataTable two = new DataTable();
two.Columns.Add("ID");
two.Columns.Add("PCT");
two.Columns.Add("OldPCT");
two.Rows.Add("1", "0.1", "0");
two.Rows.Add("2", "0.1", "0");
two.Rows.Add("3", "0.9", "0");
two.Columns.Remove("OldPCT");
//First method
DataTable three = two.AsEnumerable().Except(one.AsEnumerable()).CopyToDataTable();
foreach (DataRow dr in three.AsEnumerable())
{
string strID = dr[0].ToString();
string strPCT = dr[1].ToString();
}
//second method
var diffName = two.AsEnumerable().Select(r => r.Field<string>("PCT")).Except(one.AsEnumerable().Select(r => r.Field<string>("PCT")));
if (diffName.Any())
{
DataTable Table3 = (from row in two.AsEnumerable()
join name in diffName
on row.Field<string>("PCT") equals name
select row).CopyToDataTable();
}
So far I have tried two methods and I'm not not getting my expected result and it should be like.
In third datatable the values should be like mentioned below.
ID PCT
2 O.1
3 0.9
Recent One:
DataTable one = new DataTable();
one.Columns.Add("ID");
one.Columns.Add("PCT");
one.Rows.Add("1", "0.1");
one.Rows.Add("2", "0.2");
one.Rows.Add("2", "0.2");
one.Rows.Add("3", "0.3");
one.Rows.Add("3", "0.3");
DataTable two = new DataTable();
two.Columns.Add("ID");
two.Columns.Add("PCT");
two.Rows.Add("1", "0.1");
two.Rows.Add("2", "0.1");
two.Rows.Add("2", "0.1");
two.Rows.Add("3", "0.8");
two.Rows.Add("3", "0.9");
Now I need to get all the rows from datatable two except first row. But I am getting only last three rows.
Building on Hogan's answer, you can use DataRowComparer.Default as the second parameter to the Except() method (instead of creating a custom IEqualityComparer):
// this will get all rows from table two that don't match rows in one
// the result is an IEnumerable<DataRow>
var unmatched = two.AsEnumerable()
.Except(one.AsEnumerable(), DataRowComparer.Default);
// CopyToDataTable converts an IEnumerable<DataRow> into a DataTable
// but it blows up if the source object is empty
// this statement makes sure unmatched has data before calling CopyToDataTable()
// if it is empty, we 'clone' (make an empty copy) of one of the original DataTables
var three = unmatched.Any() ? unmatched.CopyToDataTable() : one.Clone();
This will do a value-based comparison of the fields in each row to determine if they are equal.
You need a custom IEqualityComparer
void Main()
{
DataTable one = new DataTable();
one.Columns.Add("ID");
one.Columns.Add("PCT");
one.Rows.Add("1", "0.1");
one.Rows.Add("2", "0.2");
one.Rows.Add("3", "0.3");
DataTable two = new DataTable();
two.Columns.Add("ID");
two.Columns.Add("PCT");
two.Columns.Add("OldPCT");
two.Rows.Add("1", "0.1", "0");
two.Rows.Add("2", "0.1", "0");
two.Rows.Add("3", "0.9", "0");
two.Columns.Remove("OldP
DataTable three = two.AsEnumerable().Except(one.AsEnumerable(),new RowEqualityComparer()).CopyToDataTable();
foreach (DataRow dr in three.AsEnumerable())
{
string strID = dr[0].ToString();
string strPCT = dr[1].ToString();
}
}
class RowEqualityComparer : IEqualityComparer<DataRow>
{
public bool Equals(DataRow b1, DataRow b2)
{
if ((b1.Field<string>("ID") == b2.Field<string>("ID")) && (b1.Field<string>("PCT") == b2.Field<string>("PCT")))
{
return true;
}
else
{
return false;
}
}
public int GetHashCode(DataRow bx)
{
return (bx.Field<string>("ID")+bx.Field<string>("PCT")).GetHashCode();
}
}
i have two datatable arrays
DataTable[] DTrightSplitH2;
DataTable[] DTleftSplitH2;
what i try to do is to take each datatable in DTright and compare to DTleft in "key" columns
it they are the same, merge the row
i know i should use DataTable.Merge with bool set to false and adding missing schema but i can't make it work like i want
Try this :
DTrightSplitH2.Union(DTleftSplitH2);
Sounds as if you could use my MergeAll method (usage below).
public static DataTable MergeAll(this IList<DataTable> tables, String primaryKeyColumn)
{
if (!tables.Any())
throw new ArgumentException("Tables must not be empty", "tables");
if(primaryKeyColumn != null)
foreach(DataTable t in tables)
if(!t.Columns.Contains(primaryKeyColumn))
throw new ArgumentException("All tables must have the specified primarykey column " + primaryKeyColumn, "primaryKeyColumn");
if(tables.Count == 1)
return tables[0];
DataTable table = new DataTable("TblUnion");
table.BeginLoadData(); // Turns off notifications, index maintenance, and constraints while loading data
foreach (DataTable t in tables)
{
foreach (DataColumn col in t.Columns)
col.ReadOnly = false; // required e.g. if you use a DataSet with Foreign-Key Constraints
table.Merge(t); // same as table.Merge(t, false, MissingSchemaAction.Add);
}
table.EndLoadData();
if (primaryKeyColumn != null)
{
// since we might have no real primary keys defined, the rows now might have repeating fields
// so now we're going to "join" these rows ...
var pkGroups = table.AsEnumerable()
.GroupBy(r => r[primaryKeyColumn]);
var dupGroups = pkGroups.Where(g => g.Count() > 1);
foreach (var grpDup in dupGroups)
{
// use first row and modify it
DataRow firstRow = grpDup.First();
foreach (DataColumn c in table.Columns)
{
if (firstRow.IsNull(c))
{
DataRow firstNotNullRow = grpDup.Skip(1).FirstOrDefault(r => !r.IsNull(c));
if (firstNotNullRow != null)
firstRow[c] = firstNotNullRow[c];
}
}
// remove all but first row
var rowsToRemove = grpDup.Skip(1);
foreach(DataRow rowToRemove in rowsToRemove)
table.Rows.Remove(rowToRemove);
}
}
return table;
}
Usage:
var tables = DTrightSplitH2.Concat(DTleftSplitH2).ToArray();
DataTable TblUnion = tables.MergeAll("key");
I have two datatables.
1st table-----> DataTable _dtMain = new COrder().GetDetails();
2nd table-----> DataTable _dtSub = new CGrid().GetSubDetails();
I want to add the above two tables. I am using _dtMain.Merge(_dtSub );
But it will append _dtSub table to _dtMain table. I want datatable to add second table to first table in column wise (that means after first table last column)
Don't think there any built-in method for the thing you want to achieve.
I think you need to make your own implementation for that stuff, like for example an extension method
public static DataTable Aggregate(this DataTable dt1, DataTable dt2)
{
var aggregator = new DataTable();
//add columns from dt1 and dt2
//add rows from dt1 dt2
}
or, you can do a complete Outer Join on both tables, like descrived in this article.
After a lot of research , i find out the answer for my question that i posted before. Here is the code for combing 2 datatable & the data inside it.
public DataTable CombineTable(DataTable _dtGridDetails, DataTable _dtSubGridDetails)
{
//first create the datatable columns
DataSet mydataSet = new DataSet();
mydataSet.Tables.Add(" ");
DataTable myDataTable = mydataSet.Tables[0];
//add left table columns
DataColumn[] dcLeftTableColumns = new DataColumn[_dtGridDetails.Columns.Count];
_dtGridDetails.Columns.CopyTo(dcLeftTableColumns, 0);
foreach (DataColumn LeftTableColumn in dcLeftTableColumns)
{
if (!myDataTable.Columns.Contains(LeftTableColumn.ToString()))
myDataTable.Columns.Add(LeftTableColumn.ToString());
}
//now add right table columns
DataColumn[] dcRightTableColumns = new DataColumn[_dtSubGridDetails.Columns.Count];
_dtSubGridDetails.Columns.CopyTo(dcRightTableColumns, 0);
foreach (DataColumn RightTableColumn in dcRightTableColumns)
{
if (!myDataTable.Columns.Contains(RightTableColumn.ToString()))
{
// if (RightTableColumn.ToString() != RightPrimaryColumn)
myDataTable.Columns.Add(RightTableColumn.ToString());
}
}
//add left-table data to mytable
foreach (DataRow LeftTableDataRows in _dtGridDetails.Rows)
{
myDataTable.ImportRow(LeftTableDataRows);
}
for (int nIndex = 0; nIndex <= myDataTable.Rows.Count-1; nIndex++)
{
if (nIndex == _dtSubGridDetails.Rows.Count)
break;
myDataTable.Rows[nIndex][columnindex] = _dtSubGridDetails.Rows[nIndex][columnindex];
}
return myDataTable;
}