We want to set the selection on a XtraGrid based on a List collection from the same type as the datamember of an XtraGrid.
The way we do it now is to iterate the gridview rows.
private void SetSelectedRowsInternal(IList<StrongType> collecshung)
{
grdvSomeGrid.ClearSelection();
grdvSomeGrid.BeginSelection();
for (int i = 0;i < grdvSomeGrid.RowCount;i++)
{
StrongType _strongTyped = ((StrongType)grdvSomeGrid.GetRow(i));
if (collecshung.Where(x => x.Id == _strongTyped.Id).Count() == 1)
grdvSomeGrid.SelectRow(i);
}
grdvSomeGrid.EndSelection();
}
Is there a better way to do this?
It depends on how you fill your grid ... You can directly iterate on the BindingList for instance (using LINQ). But if you find that it is taking more time than needed, then it should be because LINQ functions can be hit more than 1 million time even for a small amount of data.
I recommend you to use a dictionary instead of a LINQed collection.
Related
Hi im relatively new to c# code and i was wondering if there is any way to get the amount of columns and rows in a grid and store that amount in a variable
Something like:
var columnamount = grid.columnamount;
But i could not find anything that works
Thanks
You can use the following code to get a count of the columns and rows directly via the ColumnDefinitions and RowDefinitions properties. No need to enumerate the children of the grid because you may not have views in every column/row.
var columnCount = grid.ColumnDefintions.Count;
var rowCount = grid.RowDefinitions.Count;
For reference the documentation.
You might be able to do it this way, purely based on what I see in the docs:
var countColumns = grid.Children.Where( c => c.Column).Max();
var countRows = grid.Children.Where( c => c.Row).Max();
But I'm not sure if you can access Row anf Column properties on the child element.
This is not the best way to check, I guess, but it's working (same thing for columns):
EDIT: nope, for columns it doesn't work
int GetRowsCount(Grid grid)
{
var item = grid.Children.FirstOrDefault();
return item != null ? Grid.GetRow(item) + 1 : 0;
}
I am adding QTableWidgets to a layout (called tableArea). I have a function that I want to be able to go through all the selected items in all tables I have added to my layout:
for (int i=0; i <ui->tableArea->count(); i++)
{
QTableWidget *tableI = (QTableWidget*)ui->tableArea->itemAt(i)->widget();
int rowCount = tableI->rowCount(); // just to test if correct info
QList<QTableWidgetItem*> list = tableI->selectedItems(); // This is empty!!
}
The function iterates through correct tables, and it even knows the right row count for each table, but it doesn't seem to know which items are selected in the table. When I select items, this function doesn't seem to recognize that there is something selected. I imagine this has to do with the cast. Any idea? Thanks in advance!
This pertains to .NET Web Performance Tests.
If I have an ASP.NET page with a GridView that has a column of ints, how do I write an extraction rule to get the largest int in the column?
I tried creating a custom extraction rule by inheriting from ExtractionRule and in the Extract method using e.Response.HtmlDocument.GetFilteredHtmlTags however, the HtmlTags returned don't seem to expose their innerHtml contents.
Perhaps you can write an extraction rule that gets the whole column, then process the numbers to get their maximum value. Alternatively, use a built-in extraction rule to get the whole column, then write a plugin to get the maximum value. In either case your code should expect a mixture of numbers and other text.
Ben Day has a great blog post containing two types that express similar concerns. TableColumnValueValidator and ExtractRandomValueFromTable.
http://www.benday.com/2013/08/19/validation-extraction-rules-for-visual-studio-2012-web-performance-tests/
In the Extract(object, ExtractionEventArgs), you need to parse the ExtractionEventArgs.Response.BodyString. Ben uses the HtmlAgilityPack library for this. http://www.nuget.org/packages/htmlagilitypack
Something like this is roughly the code you'd need. This is simliar logic to ExtractRandomValueFromTable.
This does not account for thead/tbody or cells that span multiple columns/rows.
HtmlDocument doc = new HtmlAgilityPack.HtmlDocument();
doc.LoadHtml(e.Response.BodyString);
HtmlNode table = doc.GetElementbyId(TableId); // TableId is a test property
HtmlNodeCollection columns = table.SelectNodes("//th");
int columnIndex = FindColumnIndexByName(columns, ColumnName); // ColumnName is a test property
HtmlNodeCollection rows = table.SelectNodes("//tr")
int maxValue = Int32.MinValue;
foreach(HtmlNode row in rows)
{
HtmlNodeCollection cells = row.SelectNodes("./td");
// Todo check for bounds of cells here
HtmlNode cell = cells[columnIndex];
int value = Int32.MinValue;
Int32.TryParse(cell.InnerText.Trim(), out value);
maxValue = Math.Max(value, maxValue);
}
e.WebTest.Context.Add(ContextParameterName, maxValue);
int FindColumnIndexByName(HtmlNodeCollection columns, string columnName)
{
for(int i=0; i<columns.Count; i++)
if (String.Equals(columns[i].InnerText, columnName, StringComparison.OrdinalIgnoreCase))
{
return i;
}
return -1;
}
Hi
I am creating online quiz in asp.net c#. For that i have one form that displays testlist in dropdownlist & start button. After clicking 2nd form appears, 2nd form shows one label for question, radiobuttonlist for answers ,next & checkbox for review. I am creating array of random question ids in start button click event of the 1stform. when i click next button in 2nd form then next random question appears, i want array of questions those are checked for review. I used code for arrays of values ( eg.10101) 1 for true & 0 for false as follows but i want array of that question ids those are checked:
int[] a = (int[])Session["values"];//this is array of random question ids created in 1st form
int g;
if (chkmark.Checked == true)
{
g = 1;
}
else
{
g = 0;
}
int[] chkarray = new int[Convert.ToInt32(Session["Counter"]) - 1];
int[] temp1 = (int[])Session["arrofchk"];
int k, no;
if (temp1 == null)
no = 0;
else
no = temp.Length;
for (k = 0; k < no; k++)
{
chkarray[k] = temp1[k];
}
chkarray[j] = g;
Personally, i would use a Dictionary<int, bool> for this.
In the key of the dictionary, you can store the random Question ID, in the value of the pair, you can store the checked item state. It might take you more work now to refactor it, but I believe it will save you a lot of time in the end when you want to do more actions on your quiz items.
Using a dictionary - or at least a well chosen collection, I think it will be easier to get the right data back.
For your example, it can work only if the positions of both arrays are the same.
Dictionary<int, bool> quizAnswers = new Dictionary<int, bool>(); // <questionID, checked>
// Fill dictionary with questions and answers
for(int i=0;i<a.length;i++)
{
if(temp1.length > i) // Make sure we don't get an IndexOutOfBoundsException
{
quizAnswers.Add(a[i], temp1[i] == 1);
}
}
// Get Answered question in array ( LINQ )
int[] checkedAnswers = (from KeyValuePair<int, bool> pair in quizAnswers
where pair.Value == true
select pair.Key).ToArray<int>();
The reason I am using a Dictionary here, is because I personally think it's neater than having two separate arrays.
I believe you should implement a Dictionary in your quiz, in stead of those arrays. What if the array indexes don't match, or you want to dynamically add a question to a fixed size array, etc..
It's something to take into consideration. Hope I could help you out.
When i have a DataView Operation as
EnumerableRowCollection<DataRow> query
= from order in _table.AsEnumerable()
where order.Field<Int32>("key") > 2 && order.Field<Int32>("key") < 4
select order.Field<Int32>("key")=1000, order.Field<string>("name");
I can't form the above expression.
When i try
select new {key= 1000,name= order.Field<string>("name") };
i got
Cannot implicitly convert type
'System.Data.EnumerableRowCollection<AnonymousType#1>'
to 'System.Data.EnumerableRowCollection<System.Data.DataRow>'
How to form the right query? My task is to replace the key with 1000 and leave the name as is.
When you write select new {key= 1000,name= order.Field<string>("name") }, you're creating a new anonymous type that has nothing to do with DataRow.
Therefore, you can't assign it to a EnumerableRowCollection<DataRow>.
To fix the compiler error, change EnumerableRowCollection<DataRow> to var.
However, that won't fix your underlying problem.
LINQ cannot be used to modify data.
You need to use a normal foreach loop and set the key values, like this:
var affectedRows = from order in _table.AsEnumerable()
where order.Field<Int32>("key") > 2 && order.Field<Int32>("key") < 4
select row;
foreach(DataRow row in affectedRows) {
row["key"] = 1000;
}
This code will modify the original DataRows in the original _table.
If you don't want to modify the original _table, you can copy it by calling DataTable.Copy().