Error: Datatable named "Items" already belongs to this dataset - c#

Why am I receiving the error Datatable named "Items" already belongs to this dataset in the code below? The error is only occurring when I am attempting to add values where if ((x > 1) || (x == 1)). I can successfully create multiple new "Item" datatables and then add them to the ds dataset in the while loop, however trying to more than one "AItem" datatable to AllItems dataset causes the error. The only difference between these datasets is that the ds dataset has many other datatables added to it which have data adapters filling them from a SQL db.
DataSet AllItems = new DataSet("Items");
DataSet ds = new DataSet("Header");
foreach (DataRow fieldRow in myDataset.Tables["tempTable"].AsEnumerable())
{
while (x < 1)
{
x++;
DataTable Item = new DataTable("Item");
Item.Columns.Add("ID");
Item.Columns.Add("LineNumber");
Item.Columns.Add("ItemID");
Item.Columns.Add("UnitPrice");
Item.Columns.Add("Description");
Item.Columns.Add("OrderUOM");
Item.Columns.Add("OrderQty");
DataRow aItem = Item.NewRow();
Item["ID"] = 1.ToString();
Item["LineNumber"] = x;
Item["ItemID"] = fieldRow[0].ToString();
Item["UnitPrice"] = fieldRow[1].ToString();
Item["Description"] = fieldRow[2].ToString();
Item["OrderUOM"] = fieldRow[3].ToString();
Item["OrderQty"] = fieldRow[4].ToString();
Item.Rows.Add(aItem);
ds.Tables.Add(Item);
}
if ((x > 1) || (x == 1))
{
DataTable AItem = new DataTable("AItem");
Item.Columns.Add("ID");
Item.Columns.Add("LineNumber");
Item.Columns.Add("ItemID");
Item.Columns.Add("UnitPrice");
Item.Columns.Add("Description");
Item.Columns.Add("OrderUOM");
Item.Columns.Add("OrderQty");
DataRow aItem = Item.NewRow();
Item["ID"] = 1.ToString();
Item["LineNumber"] = x;
Item["ItemID"] = fieldRow[0].ToString();
Item["UnitPrice"] = fieldRow[1].ToString();
Item["Description"] = fieldRow[2].ToString();
Item["OrderUOM"] = fieldRow[3].ToString();
Item["OrderQty"] = fieldRow[4].ToString();
Item.Rows.Add(aItem);
AllItems.Tables.Add(AItem);
}
}

I'm not sure if this is your only problem but you are using the DataTable as if it was a DataRow. Item is the table, it has no string-indexer, so replace
DataRow aItem = Item.NewRow();
Item["ID"] = 1.ToString();
Item["LineNumber"] = x;
Item["ItemID"] = fieldRow[0].ToString();
Item["UnitPrice"] = fieldRow[1].ToString();
Item["Description"] = fieldRow[2].ToString();
Item["OrderUOM"] = fieldRow[3].ToString();
Item["OrderQty"] = fieldRow[4].ToString();
Item.Rows.Add(aItem);
with
DataRow aItem = Item.NewRow();
aItem["ID"] = 1.ToString();
aItem["LineNumber"] = x;
aItem["ItemID"] = fieldRow[0].ToString();
aItem["UnitPrice"] = fieldRow[1].ToString();
aItem["Description"] = fieldRow[2].ToString();
aItem["OrderUOM"] = fieldRow[3].ToString();
aItem["OrderQty"] = fieldRow[4].ToString();
Item.Rows.Add(aItem);
But i assume that this is just the next error, "Datatable named “Items” already belongs to this dataset" is thrown because you are adding a table to a DataSet with the same name of another table. You are adding tables with the static name "AItem" in the loop here:
foreach (DataRow fieldRow in myDataset.Tables["tempTable"].AsEnumerable())
{
// ...
DataTable AItem = new DataTable("AItem");
// ...
AllItems.Tables.Add(AItem);
// ...
}
I don't understand the logic, maybe it's sufficient to use the default constructor without a name.

Related

I need helping adding two different rows(with same columns) to the same datatable

Working on a windows form application that reads in data from csv files and adds the data to a Datagridview. I ran into an issue with all of the rows being added to the datable and being displayed on the datagridview. The datagridview displays the datarows from the first two if conditions and OneRow if condition only. It will not add the rows from the twoRow if condition if the datable and datagridview rows are populated with the OneRow if condition rows. But i want the rows from both OneRow and TwoRow to be displyed. Also the rows from TwoRow do populate the datatable and datagridview when I comment(/**/) out the OneRow if condition. But I need both to populate the table. Thanks in advance!
Construct.MainDataTable.Columns.Add("Date", typeof(DateTime));
Construct.MainDataTable.Columns.Add("Time");
Construct.MainDataTable.Columns.Add("Serial");
Construct.MainDataTable.Columns.Add("Type");
Construct.MainDataTable.Columns.Add("level");
Construct.MainDataTable.Columns.Add("price");
Construct.MainDataTable.Columns.Add(" Limit");
Construct.MainDataTable.Columns.Add("last Limit");
Construct.MainDataTable.Columns.Add("Data");
..........................
...............................................
DataRow oneRow = Construct.MainDataTable.NewRow();
DataRow twoRow = Construct.MainDataTable.NewRow();
dataGridView2.AllowUserToAddRows = false;
if (line.Split(',')[2].Equals("Time"))
{
time = line.Split(',')[3];
date = line.Split(',')[1];
}
if (line.Split(',')[2].Equals("Level"))
{
level = line.Split(',')[3];
}
//OneROw(IF condition)
if ((Convert.ToDecimal(line.Split(',')[8])) < (Convert.ToDecimal (line.Split(',')[12])))
{
type = line.Split(',')[1];
serial = line.Split(',')[7];
price = line.Split(',')[3];
Limit = line.Split(',')[8];
lastLimit = line.Split(',')[10];
Data = line.Split(',')[12];
oneRow["Date"] = date;
oneRow["Time"] = time;
oneRow["Serial"] = serial;
oneRow["Type"] = type;
oneRow["level"] = level;
oneRow["price"] = price;
oneRow[" Limit"] = Limit;
oneRow["last Limit"] = lastlimit;
oneRow["Data"] = Data;
Construct.MainDataTable.Rows.Add(oneRow);
}
//TwoROw(IF condition)
if ((line.Contains('"')) && ((line.Contains("NG"))))
{
price = line.Split(',')[3];
type = line.Split(',')[1];
serial = line.Split(',')[7];
Limit = line.Split('"')[7];
var valLimit = Limit.Split(',').Select(a => Convert.ToInt32(a, 16));
var limitJoin = String.Join(",", valLimit);
lastlimit = line.Split('"')[1];
var vallastLimit = lastlimit.Split(',').Select(d => Convert.ToInt32(d, 16));
var lastJoin = String.Join(",", vallastLimit);
Data = line.Split('"')[5];
var valDatas = Data.Split(',').Select(s => Convert.ToInt32(s, 16));
var dataJoin = String.Join(",", valDatas);
twoRow["Date"] = date;
twoRow["Time"] = time;
twoRow["Serial"] = serial;
twoRow["Type"] = type;
twoRow["level"] = level;
twoRow["price"] = price;
twoRow["Limit"] = limitJoin;
twoRow["last Limit"] = lastJoin;
twoRow["Data"] = dataJoin;
Construct.MainDataTable.Rows.Add(twoRow);
}
dataGridView2.DataSource = Construct.MainDataTable;
Can't add a comment because I don't have enough karma so I ask my questions here: So, if I understood your problem you can't add data from one .csv file if it have more then one row? Why are you using 2 different if conditions for row in .csv file?
If you have empty data in row never mind you can still place them to your DataTable column, so you can use loop to add data from .csv to your DataTable. Try some thing like this:
public static DataTable CsvToDataTable(string csv)
{
DataTable dt = new DataTable();
string[] lines = csv.Split(new[] { "\r\n", "\r", "\n" }, StringSplitOptions.RemoveEmptyEntries);
Regex onlyDeimiterComma = new Regex(",(?=(?:[^\"]*\"[^\"]*\")*(?![^\"]*\"))");
for (int i = 0; i < lines.Length; i++)
{
DataRow row = dt.NewRow();
string[] cells = onlyDeimiterComma.Split(lines[i]);
for (int j = 0; j < cells.Length; j++)
{
if (i == 0)
{
if (j == 0)
{
dt.Columns.Add(cells[j], typeof(DateTime));
}
else
{
dt.Columns.Add(cells[j]);
}
}
else
{
row[j] = cells[j];
}
}
dt.Rows.Add(row);
}
return dt;
}
Just call this method anywhere in your code and give it string read from your .csv file.
You can try to compile this code here and see how it works on .csv data with different data (empty columns, quoted text, quoted commas)
UPD: If you need to fill DataTable from two different .csv files you can still use code above. Just call it twice for both files and then Merge two DataTable, like this:
DataTable dt = CsvToDataTable(csvFileOne);
DataTable dtTwo = CsvToDataTable(csvFileTwo);
dt.Merge(dtTwo);

Merge two datatable to one based on column

this question has been asked but mine has a different approach link 1
l have a datatable with the following data
DataTable dtProduct = new DataTable();
dtProduct.Columns.Add("productId");
dtProduct.Columns.Add("name");
DataRow dataRow = dtProduct.NewRow();
dataRow["productId"] = 1;
dataRow["name"] = "Burger";
dtProduct.Rows.Add(dataRow);
DataRow dataRow2 = dtProduct.NewRow();
dataRow2["productId"] = 2;
dataRow2["name"] = "Chicken";
dtProduct.Rows.Add(dataRow2);
DataTable dtSales = new DataTable();
dtSales.Columns.Add("productId");
dtSales.Columns.Add("saleId");
dtSales.Columns.Add("month");
dtSales.Columns.Add("quantity");
DataRow dataSalesRow = dtSales.NewRow();
dataSalesRow["productId"] = 1;
dataSalesRow["saleId"] = "1";
dataSalesRow["month"] = "Jan";
dataSalesRow["quantity"] = 3433;
dtSales.Rows.Add(dataSalesRow);
DataRow drSales2 = dtSales.NewRow();
drSales2["productId"] = 1;
drSales2["saleId"] = "2";
drSales2["month"] = "Feb";
drSales2["quantity"] = 56;
dtSales.Rows.Add(drSales2);
DataRow drSales3 = dtSales.NewRow();
drSales3["productId"] = 1;
drSales3["saleId"] = "3";
drSales3["month"] = "Mar";
drSales3["quantity"] = 34522;
dtSales.Rows.Add(drSales3);
DataRow drSales4 = dtSales.NewRow();
drSales4["productId"] = 2;
drSales4["saleId"] = "4";
drSales4["month"] = "Feb";
drSales4["quantity"] = 345;
dtSales.Rows.Add(drSales4);
And another sample 2
DataTable dtStudents = new DataTable();
dtStudents.Columns.Add("studentId");
dtStudents.Columns.Add("fullname");
DataRow drStudentrow = dtStudents.NewRow();
drStudentrow["studentId"] = 1;
drStudentrow["fullname"] = "Bil";
dtStudents.Rows.Add(drStudentrow);
DataRow drStudentrow2 = dtStudents.NewRow();
drStudentrow2["studentId"] = 2;
drStudentrow2["fullname"] = "Paul";
dtStudents.Rows.Add(drStudentrow2);
DataTable dtStudentExam = new DataTable();
dtStudentExam.Columns.Add("studentId");
dtStudentExam.Columns.Add("subjectId");
dtStudentExam.Columns.Add("mark");
DataRow dataStudentExamRow = dtStudentExam.NewRow();
dataStudentExamRow["studentId"] = 1;
dataStudentExamRow["subjectId"] = "E123";
dataStudentExamRow["mark"] = 34;
dtStudentExam.Rows.Add(dataStudentExamRow);
DataRow dataStudentExamRow2 = dtStudentExam.NewRow();
dataStudentExamRow2["studentId"] = 2;
dataStudentExamRow2["subjectId"] = "E123";
dataStudentExamRow2["mark"] = 90;
dtStudentExam.Rows.Add(dataStudentExamRow2);
DataRow dataStudentExamRow3 = dtStudentExam.NewRow();
dataStudentExamRow3["studentId"] = 1;
dataStudentExamRow3["subjectId"] = "E155";
dataStudentExamRow3["mark"] = 78;
dtStudentExam.Rows.Add(dataStudentExamRow3);
DataRow dataStudentExamRow4 = dtStudentExam.NewRow();
dataStudentExamRow4["studentId"] = 1;
dataStudentExamRow4["subjectId"] = "E101";
dataStudentExamRow4["mark"] = 12;
dtStudentExam.Rows.Add(dataStudentExamRow4);
DataRow dataStudentExamRow5 = dtStudentExam.NewRow();
dataStudentExamRow5["studentId"] = 1;
dataStudentExamRow5["subjectId"] = "E234";
dataStudentExamRow5["mark"] = 42;
dtStudentExam.Rows.Add(dataStudentExamRow5);
DataTable products(dtProduct ) has a productId which is the key and another data table sales (dtSales) has sales for the product based on month . and has a column productId .
what l want to achieve is merge this two tables to this
Same Applies for students
l have a data table student (dtStudents) but l however l have student exam marks data tables (dtStudentExam) for each subject
and combine to something like this
So my question is can l do this dynamically . l tried the following below
public static System.Data.DataTable MergeRowsToColumns(DataTable rowDataTable, string rowDataTableIdColumnName, string friendlyName, DataTable columData)
{
List<string> columnsToAdd = new List<string>();
if (rowDataTable == null)
{
return null;
}
DataTable finalDataTable = new DataTable();
finalDataTable.Columns.Add(friendlyName.ToLower());
finalDataTable.Columns.Add(rowDataTableIdColumnName.ToLower());
foreach (DataColumn column in columData.Columns)
{
if (column.ColumnName.ToString() == rowDataTableIdColumnName.ToString())
{
continue;
}
else
{
finalDataTable.Columns.Add(column.ColumnName.ToString());
columnsToAdd.Add(column.ColumnName.ToString());
}
}
foreach (DataRow row in rowDataTable.Rows)
{
DataRow newRow = finalDataTable.NewRow();
newRow[rowDataTableIdColumnName] = row[rowDataTableIdColumnName];
newRow[friendlyName] = row[friendlyName];
foreach (DataRow columnRows in columData.Rows)
{
foreach (string column in columnsToAdd)
{
var value = columnRows[column].ToString();
newRow[column] = value;
}
}
finalDataTable.Rows.Add(newRow);
}
return finalDataTable;
}
Algorithm logic
Table 1 holds the key information
Table 2 holds the value data for table
using a column name from table one for id which will be the same on table 2
can l do it generically
in one function like
var dtMergedProducts = HelperDataTable.MergeRowsToColumns(dtProduct, "productId", "name", dtSales);
var dtStudents = HelperDataTable.MergeRowsToColumns(dtStudents, "studentId", "fullname", dtStudentExam);
Please am retrieving the data as is hence can not group by in table 2 and also table two does not have a friendly name that will be displayed.
Most of the data that is loaded is not more than 100 000
this is the link of the helper utility am making git hub
Edit One
DataTable 2 will have column value one for column and the other for value
For example
dtSales
1- month : shown vertically
2- quantity: will be cell value
Sample 2
dtStudentExam
1- subjectId : shown vertically
2- mark : will be the student mark
l got it working this morning
here if the method
public static System.Data.DataTable MergeRowsToColumns(DataTable rowDataTable, string rowDataTableIdColumnName, string friendlyName, DataTable dataAllValue , string dataColumnValue , string dataColumnKey)
{
List<string> columnsToAdd = new List<string>();
if (rowDataTable == null)
{
return null;
}
DataTable finalDataTable = new DataTable();
finalDataTable.Columns.Add(friendlyName.ToLower());
finalDataTable.Columns.Add(rowDataTableIdColumnName.ToLower());
foreach (DataRow row in dataAllValue.Rows)
{
if (row[rowDataTableIdColumnName].ToString() == rowDataTableIdColumnName.ToString())
{
continue;
}
else
{
var isExistColumnValue = columnsToAdd.Where(c => c == row[dataColumnKey].ToString()).FirstOrDefault();
if(isExistColumnValue == null)
{
columnsToAdd.Add(row[dataColumnKey].ToString());
finalDataTable.Columns.Add(row[dataColumnKey].ToString());
}
}
}
foreach (DataRow row in rowDataTable.Rows)
{
DataRow newRow = finalDataTable.NewRow();
newRow[rowDataTableIdColumnName] = row[rowDataTableIdColumnName];
newRow[friendlyName] = row[friendlyName];
foreach (DataRow columnRows in dataAllValue.Rows)
{
if(row[rowDataTableIdColumnName].ToString() != columnRows[rowDataTableIdColumnName].ToString())
{
continue;
}
var columnName = columnRows[dataColumnKey].ToString();
var columnValue = columnRows[dataColumnValue].ToString();
newRow[columnName] = columnValue;
}
finalDataTable.Rows.Add(newRow);
}
return finalDataTable;
}
it looked like l was failing on adding the column names before merging
you can just call like
var dt = HelperDataTable.MergeRowsToColumns(dtProduct, "productId", "name", dtSales , "quantity", "month");
var dt2 = HelperDataTable.MergeRowsToColumns(dtStudents, "studentId", "fullname", dtStudentExam , "mark", "subjectId");

How to load column data from DataReader?

I'm porting application to ASP.Net 5.0 with EF7 and found several problems. One of the issues is MS have dropped DataTable. I'm trying to transfer a bit of code to not use DataTable but read from SQLDataReader and record this into entities I have. I have to read data by columns, but looks like datareader can read only once.
The old code:
Series[] arrSeries = new Series[dt.Columns.Count - 1];
IList<Categories> arrCats = new List<Categories>();
Categories arrCat = new Categories();
foreach (DataColumn dc in dt.Columns)
{
var strarr = dt.Rows.Cast<DataRow>().Select(row => row[dc.Ordinal]).ToList();
if (dc.Ordinal == 0)
{
arrCat.category = strarr.Select(o => new Category { label = o.ToString() }).ToList();
}
else
{
Series s = new Series()
{
seriesname = dc.ColumnName,
renderas = null,
showvalues = false,
data = strarr.Select(o => new SeriesValue { value = o.ToString() }).ToList()
};
arrSeries[dc.Ordinal - 1] = s;
}
}
arrCats.Add(arrCat);
MultiFusionChart fusChart = new MultiFusionChart
{
chart = dictAtts,
categories = arrCats,
dataset = arrSeries
};
return fusChart;
The new code:
Series[] arrSeries = new Series[colColl.Count - 1];
IList<Categories> arrCats = new List<Categories>();
Categories arrCat = new Categories();
arrCat.category = new List<Category>();
for (int i = 0; i < reader.FieldCount; i++)
{
Series s = new Series()
{
seriesname = reader.GetName(i),
renderas = null,
showvalues = false
};
while (reader.Read())
{
if (i == 0)
{
Category cat = new Category();
cat.label = reader.GetValue(i).ToString();
arrCat.category.Add(cat);
}
else
{
SeriesValue sv = new SeriesValue();
sv.value = reader.GetValue(i).ToString();
s.data.Add(sv);
arrSeries[i - 1] = s;
}
}
}
arrCats.Add(arrCat);
MultiFusionChart fusChart = new MultiFusionChart
{
chart = dictAtts,
categories = arrCats,
dataset = arrSeries
};
return fusChart;
Where the code works, it returns null for Series. And I believe this is because reader went to the end while recording Categories. As far as I know it is not possible to reset DataReader?
Is there a way to load column data from DataReader to List? Or maybe there is other way how I can replace DataTable in this example?
You can read value from multiple columns by specifying its index like this
int totalColumns = reader.FieldCount;
for(int i=0;i<totalColumns;i++)
{
var label = reader.GetValue(i);
}
You can select value of all columns by looping through columns.
GetValue takes int as argument which is index of column not the index of row.
The problem is in your for loop. At first when your i is 0, You have initialized a 'Series` object S. After that,
while (reader.Read())
will read your entire Reader while your i will still be zero. SO only the
if(i == 0)
condition will return true and your entire reader will be spent. Afterwards, for i >= 1,
while (reader.Read())
will always return false keeping your array, arrSeries blank. Remove the while loop and directly read value from the dataReader using the index,
reader.GetValue(i);

Use linq to find DataTable(Name) in a DataSet using unique list of Column Names

I got roped into some old code, that uses loose (untyped) datasets all over the place.
I'm trying to write a helper method to find the DataTable.Name using the names of some columns.....(because the original code has checks for "sometimes we have 2 datatables in a dataset, sometimes 3, sometimes 4)..and its hard to know the order. Basically, the TSQL Select statements conditionally run. (Gaaaaaaaaaaaaaahhh).
Anyway. I wrote the below, and if I give it 2 column names, its matching on "any" columnname, not "all column names".
Its probably my linq skillz (again), and probably a simple fix.
But I've tried to get the syntax sugar down..below is one of the things I wrote, that compiles.
private static void DataTableFindStuff()
{
DataSet ds = new DataSet();
DataTable dt1 = new DataTable("TableOne");
dt1.Columns.Add("Table1Column11");
dt1.Columns.Add("Name");
dt1.Columns.Add("Age");
dt1.Columns.Add("Height");
DataRow row1a = dt1.NewRow();
row1a["Table1Column11"] = "Table1Column11_ValueA";
row1a["Name"] = "Table1_Name_NameA";
row1a["Age"] = "AgeA";
row1a["Height"] = "HeightA";
dt1.Rows.Add(row1a);
DataRow row1b = dt1.NewRow();
row1b["Table1Column11"] = "Table1Column11_ValueB";
row1b["Name"] = "Table1_Name_NameB";
row1b["Age"] = "AgeB";
row1b["Height"] = "HeightB";
dt1.Rows.Add(row1b);
ds.Tables.Add(dt1);
DataTable dt2 = new DataTable("TableTwo");
dt2.Columns.Add("Table2Column21");
dt2.Columns.Add("Name");
dt2.Columns.Add("BirthCity");
dt2.Columns.Add("BirthState");
DataRow row2a = dt2.NewRow();
row2a["Table2Column21"] = "Table2Column1_ValueG";
row2a["Name"] = "Table2_Name_NameG";
row2a["BirthCity"] = "BirthCityA";
row2a["BirthState"] = "BirthStateA";
dt2.Rows.Add(row2a);
DataRow row2b = dt2.NewRow();
row2b["Table2Column21"] = "Table2Column1_ValueH";
row2b["Name"] = "Table2_Name_NameH";
row2b["BirthCity"] = "BirthCityB";
row2b["BirthState"] = "BirthStateB";
dt2.Rows.Add(row2b);
ds.Tables.Add(dt2);
DataTable dt3 = new DataTable("TableThree");
dt3.Columns.Add("Table3Column31");
dt3.Columns.Add("Name");
dt3.Columns.Add("Price");
dt3.Columns.Add("QuantityOnHand");
DataRow row3a = dt3.NewRow();
row3a["Table3Column31"] = "Table3Column31_ValueM";
row3a["Name"] = "Table3_Name_Name00M";
row3a["Price"] = "PriceA";
row3a["QuantityOnHand"] = "QuantityOnHandA";
dt3.Rows.Add(row3a);
DataRow row3b = dt3.NewRow();
row3b["Table3Column31"] = "Table3Column31_ValueN";
row3b["Name"] = "Table3_Name_Name00N";
row3b["Price"] = "PriceB";
row3b["QuantityOnHand"] = "QuantityOnHandB";
dt3.Rows.Add(row3b);
ds.Tables.Add(dt3);
string foundDataTable1Name = FindDataTableName(ds, new List<string> { "Table1Column11", "Name" });
/* foundDataTable1Name should be 'TableOne' */
string foundDataTable2Name = FindDataTableName(ds, new List<string> { "Table2Column21", "Name" });
/* foundDataTable1Name should be 'TableTwo' */
string foundDataTable3Name = FindDataTableName(ds, new List<string> { "Table3Column31", "Name" });
/* foundDataTable1Name should be 'TableThree' */
string foundDataTableThrowsExceptionName = FindDataTableName(ds, new List<string> { "Name" });
/* show throw exception as 'Name' is in multiple (distinct) tables */
}
public static string FindDataTableName(DataSet ds, List<string> columnNames)
{
string returnValue = string.Empty;
DataTable foundDataTable = FindDataTable(ds, columnNames);
if (null != foundDataTable)
{
returnValue = foundDataTable.TableName;
}
return returnValue;
}
public static DataTable FindDataTable(DataSet ds, List<string> columnNames)
{
DataTable returnItem = null;
if (null == ds || null == columnNames)
{
return null;
}
List<DataTable> tables =
ds.Tables
.Cast<DataTable>()
.SelectMany
(t => t.Columns.Cast<DataColumn>()
.Where(c => columnNames.Contains(c.ColumnName))
)
.Select(c => c.Table).Distinct().ToList();
if (null != tables)
{
if (tables.Count <= 1)
{
returnItem = tables.FirstOrDefault();
}
else
{
throw new IndexOutOfRangeException(string.Format("FindDataTable found more than one matching Table based on the input column names. ({0})", String.Join(", ", columnNames.ToArray())));
}
}
return returnItem;
}
I tried this too (to no avail) (always has 0 matches)
List<DataTable> tables =
ds.Tables
.Cast<DataTable>()
.Where
(t => t.Columns.Cast<DataColumn>()
.All(c => columnNames.Contains(c.ColumnName))
)
.Distinct().ToList();
To me sounds like you're trying to see if columnNames passed to the method are contained within Column's name collection of Table. If that's the case, this should do the work.
List<DataTable> tables =
ds.Tables
.Cast<DataTable>()
.Where(dt => !columnNames.Except(dt.Columns.Select(c => c.Name)).Any())
.ToList();
(Below is an append by the asker of the question)
Well, I had to tweak it to make it compile, but you got me there..
Thanks.
Final Answer:
List<DataTable> tables =
ds.Tables.Cast<DataTable>()
.Where
(dt => !columnNames.Except(dt.Columns.Cast<DataColumn>()
.Select(c => c.ColumnName))
.Any()
)
.ToList();
Final Answer (which is not case sensitive):
List<DataTable> tables =
ds.Tables.Cast<DataTable>()
.Where
(dt => !columnNames.Except(dt.Columns.Cast<DataColumn>()
.Select(c => c.ColumnName), StringComparer.OrdinalIgnoreCase)
.Any()
)
.ToList();

DataGridView - Parent to Child Database Relation - Updating child DataGridView data

Would someone kindly assist me with the following? I have two DataGridView objects that each display a DataTable, where the two datatables are related with the following code:
DataSet dSet = new DataSet();
DataTable ParentList = ListToDataTable(_listOfAllAlbumObjects);
DataTable ChildList = ListToDataTable(_listOfAllTrackObjects);
dSet.Tables.AddRange(new DataTable[]{ParentList, ChildList});
DataColumn parentRelationColumn = ParentList.Columns["AlbumId"];
DataColumn childRelationColumn = ChildList.Columns["AlbumId"];
dSet.Relations.Add("ParentToChild", parentRelationColumn, childRelationColumn);
ParentDataGridView.DataSource = dSet;
ParentDataGridView.DataMember = "ParentList";
ChildDataGridView.DataSource = ???;
ChildDataGridView.DataMember = "ParentToChild";
Both DataTables are actually List<> converted to DataTables with the following:`
public static DataTable ListToDataTable<T>( IList<T> data)
{
var props = TypeDescriptor.GetProperties(typeof(T));
var table = new DataTable();
for (var i = 0; i < props.Count; i++)
{
PropertyDescriptor prop = props[i];
table.Columns.Add(prop.Name, prop.PropertyType);
}
var values = new object[props.Count];
foreach (T item in data)
{
for (int i = 0; i < values.Length; i++)
{ values[i] = props[i].GetValue(item); }
table.Rows.Add(values);
}
return table;
}
Initially it appears that the each DataGridView displays the data appropriately; however the child DataGridView does not update with any change of record in the parent DataGridView.
I see that the tables need to be interconnected through the binding-source; however I don't believe there is a true binding-source here.
Could someone please steer me in the right direction? Thanks.
There's an MSDN article showing what you want to do:
How to: Create a Master/Detail Form Using Two Windows Forms DataGridView Controls
Here's how this might work for you:
Either through the designer or through code add two BindingSources to your project: parentBindingSource and childBindingSource. Then try this in place of the code you have.
// Associate your BSs with your DGVs.
ParentDataGridView.DataSource = parentBindingSource;
ChildDataGridView.DataSource = childBindingSource;
// (Most of) your code here:
DataSet dSet = new DataSet();
DataTable ParentList = ListToDataTable(_listOfAllAlbumObjects);
DataTable ChildList = ListToDataTable(_listOfAllTrackObjects);
dSet.Tables.AddRange(new DataTable[]{ParentList, ChildList});
DataColumn parentRelationColumn = ParentList.Columns["AlbumId"];
DataColumn childRelationColumn = ChildList.Columns["AlbumId"];
dSet.Relations.Add("ParentToChild", parentRelationColumn, childRelationColumn);
// Let's name this DT to make clear what we're referencing later on.
ParentList.TableName = "ParentListDT";
// Rather than set the data properties on your DGVs, set them in your BindingSources.
parentBindingSource.DataSource = dSet;
parentBindingSource.DataMember = "ParentListDT";
childBindingSource.DataSource = parentBindingSource;
childBindingSource.DataMember = "ParentToChild";

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