I have a List (Of Type) which contains many instances of a class with three properties, IPAddress, AlertDate and AlertTime.There can be many duplicates of IPAddress in this list :-
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I need to be able to pull out just the latest (by date and time) entry in the list for each unique IPAddress. Is there any simple way of doing this?
I'm trying to categorize articles by stored keywords. I have a list of keywords for a category, and I want an article to get assigned a category that has the most keyword count.
For Each keyword As String In category.Keywords
category.tempCount += Regex.Matches(article.Item("title").InnerXml, Regex.Escape(keyword)).Count
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I am having so trouble with the ToUpper() procedure with strings. I am using LINQ to find unique values in a list of objects. In that whole process I set the values to compare to all lowercase in order to get a proper list. My goal is to populate a dropdown list with the values. I'm attempting to set the first letter of of the string to uppercase and keep the rest lowercase however the toUpper() procedure is not working?
Private Function FixCase(ByVal strIn) As String
Dim strOutput As String
Dim intStringLength As Integer = strIn.Length - 1
strOutput = strIn.Substring(0, 1)
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I'm having a bit of a 'brain doner' moment here
I have a list of Objects. Each of these Objects contains a list of other Objects (pseudo code) :-
Private Structure Object1
dim Name as string
dim ListOfObject2 as List(Of Object2)
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I need to sort the list of Object1 by the Value in Object2. I have a comparison class which sorts Object2 by its Value nicely.
We have a generic List(Of Product) that must be sorted on two or more properties of the Product class.
The product class has the properties "Popular" numeric (asc), "Clicked" numeric (desc), "Name" string (asc). In order of naming the properties we want the list to sort.
How can it be sort with an lamba statement? If have found to sort the list based on one property.
I have a stored procedure (I cannot edit) that I am calling via linq.
The stored procedure returns values (more complex but important data below):
Customer Stock Item Date Price Priority Qty
--------------------------------------------------------
CUST1 TAP 01-04-2012 £30 30 1 - 30
CUST1 TAP 05-04-2012 £33 30 1 - 30
CUST1 TAP 01-04-2012 £29 20 31 - 99
CUST1 TAP 01-04-2012 £28 10 1 - 30
I am trying to limit this list to rows which have unique Dates and unique quantities in LINQ. I want to remove items with the HIGHER priority leaving rows with unique dates and qty's.
I have tried several group by's using Max and order by's but have not been able to get a result.
Is there any way to do this via linq?
EDIT:
Managed to convert brad-rem's answer into VB.net.
Syntax below if anyone needs it:
returnlist = (From p In returnlist
Order By p.Qty Ascending, p.Priority
Group By AllGrp = p.Date, p.Qty Into g = Group
Select g.First).ToList
I'm using the datagridview. This is the sample data:
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How do I parse through the grid to rename the duplicate values in a particular column (in this example it's the l_name field) into such a format?
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How can I sort data in a sorted list using values instead of keys from highest to lowest?[code]...
View 2 RepliesI am using crystal reports in visual studio 2005 to generate invoices. I want to sort different categories of products. I'm using group by on category field. How can i set a specified order in crystal reports for categories.I have for example 3 categories namely 'Recipe', 'Plain Spices', and 'Horeca'....The crystal reports shows them in ascending or descending order but i want Recipe data at top, then Plain Spices and Horeca in the end...!!How can I achieve this in my crystal report that has already been made?
View 2 RepliesUnique constraint - these columns currently doesn't have unique values..?? I have created Unique Constraint with 3 columns. My code works perfectly but once - two users @ same time entered same data and somehow it saved in DB; after that incident. This UniqueConstraint gives me error - These columns currently doesn't have unique values. How can I check if user enters this kind of entry or how can I restrict the Entry?
View 2 RepliesIf I create a list for a TextBox:
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I am able to only add controls that are of type TextBox. My question to you is, can I create a List to hold more than one control type or do I have to create a list for each control type?
i have a for loop retrive me sum of colums but i need to pass these values in array list to caluclute sum of each sport type
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I have a MyObject; myObjects as List(Of MyObject) and a delegate Comparison(Of MyObject) that uses a lot of comparison functions (ByA, ByB, ByC etc) Ã la:
Shared Function CompareMyObjectsByName(x As MyObject, y As MyObject) As Integer
Return x.Name.CompareTo(y.Name)
End Function
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I have a List(Of T) storing a list of Custom classes called Advertisement. Each advertisement contains 3 properties, Year, Make and Model. I need to sort the list By Year, then by Make and then by Model. I have a property in the Advertisement class called Vehicle which returns a formatted string with the Year Make Model like 2007 Toyota Tacoma and ive been sorting on that but its not working how I thought it would. Basically I want to sort the list by Year (decending; lowest year first) then sort by the Make and Model (in alphabetical order) Is that even possible? Here is the code ive been using.
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I have some ActiveX that was written for VB6. They all seem to return Variant types. Ex.
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In this case the GetPosition control is returning a robot axis position. It looks to me like the values coming back from the function is not getting converted to object type properly.
is there a way to filter out unique values in a dataview or an array? I currently filter a dataview as such: [code] So now I have a dataview filtering the table, but can I further filter this data to find the unique instances of an item in this table? I eventually have to pass a portion of this table to an array, so if there is a way to find unique values in an array, I can use that.
View 1 Repliesis there a way to filter out unique values in a dataview or an array? I currently filter a dataview as such:
TxtString = "Name = '" & TxtName & "'AND EmpID = '" & EmpID & "'"
dv.Table = dsTestTable.Tables("TestTable")
dv = New DataView(dsTestTable.Tables(0), TxtString, "", DataViewRowState.CurrentRows
So now I have a dataview filtering the table, but can I further filter this data to find the unique instances of an item in this table? I eventually have to pass a portion of this table to an array, so if there is a way to find unique values in an array, I can use that.
how to fix it : These columns don't currently have unique values.
What should i do with my database. I'm using VB.net 2005 and SQL
I am trying to store 5 values and an associated unique key. I need to search for this key and update the 5 associated values. I'm guessing I would use an object as the value but how do I get the values out from the object?
View 19 RepliesI am using a DataGridView that has a filtered dataset and I like to validate a column in a new or changed row via a sub in the partial dataset class so that I can set the errorprovider to an error if the entered value isn't unique.I started out to set the field in SQL server with a unique key and then catch the sqlerror on the form. But data validation is best practice to do in the partial dataset class so I am trying to do it for this particular problem aswell. But after spending a lot of time I am stuck and wonder if it is even possible to do this particular validation in the partial class?
View 9 RepliesI am using XtraGrid in my application. Now, I want to display only Unique values for particular column when user will click filter button. I want to display this list check box items initially all checked. Also I want the information that what items user has selected/deselected from from checked list box.
View 1 RepliesI need to create an array, then iterate through a string, adding the string value to the array only is it does not already exist, to produce an array of unique values. The issue I am having is with the array.length operation - on a array that is nothing I am unable to retrieve the array length (0), as such I am unable to redimensionalise the array to be array length (must be array length as arrays are indexed from 0), providing me the ability to add the new value to the array and then continue the loop until all values have been checked to see if they exist within the array (using contains) and the value contain only unique values..
View 2 RepliesI'm using vb2005. I'm writing a little application which allows a person to type in a new value in a combobox (which I've bound to a field in a table) which can be updated to the database. I then refresh the dataAdapter by clearing it and re-filling it again when the user saves a new item. That part works fine. My problem occurs when the user selects a stationary item from the combobox. The first select works fine until they try to select another item. Then I get the following error: ConstraintException was unhandled: Column 'TYPE' is constrained to be unique. Value 'False' is already present.
View 2 RepliesIs there a way to get a subset of Unique values in column(1) of a DataView?
View 6 RepliesI am trying to populate an array with all the unique values in a string, to prevent me ReDim'ing an array every time I find a value that not already contained in the array I am trying to create (consumes alot of time), I am trying to get the unique values first so I only have to ReDim once and after that I can simply iterate through the string and the array I have will be the correct size for the unique values I aquire (I am using this...)
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I'm trying to make a method that can get unique values from a specified column of a DataTable. The problem is that the column may be string, integer, etc. I'm not sure what type of variable the (Of T) is.
Private Sub GetColumnUnique(ByVal dbTable As DataTable, ByVal ColumnNumber As Integer, ByVal ColumnType As ???)
Dim results As List(ColumnType) = (From item In dbTable.AsEnumerable Select item.Field(ColumnType)(ColumnNumber)).Distinct.ToList
End Sub
Is there any way to set a column to accept only unique values?(Via Table Definition)
View 2 RepliesI'm using MySQL to store some numbers. One of the columns in the database is defined as unique, but it does allow multiple NULL-values. That is exactly how I want it.ut when I'm trying to load the data into my strongly typed DataSet, I get a error saying that a constraint fails... I do understand why that happens (several rows with NULL-values in a unique column), but is it a way to keep a DataColumn in vb.net unique, but still allow several rows with NULL-values like in MySQL?
View 2 RepliesI'm using an Infragistics UltraWinGrid with a column of drop-down boxes. I don't want the user to be able to select the same value for multiple rows in that column. Is there a simple (or heck, I'd settle for advanced) way to do this? I'm using VB.NET
-EDIT-
I tried setting a filter on the data source for the drop-down box. But when I did that, the values in the other boxes in that column started disappearing (not the values themselves, but the descriptions that they were supposed to represent, so instead of reading "Information", it just said "1"). All of the cells in a column refer to the same combo box, so if you filter out a value from the data source for one of them, you filter it out for all of them. I'm currently trying to catch a CellChange event and check against all other currently-used values. If it was already used, I would put up a message saying as much and revert back to the old value. However, the value comes back as the previously-saved one, so... not helpful. About to see if I can use the "text" property.
I am new to VB.NET 2008 and a few users on this forum have suggested using Generic Lists instead of the old VB6 model of Collections. I need to add to the list of several items to the list, but what is happening it it is changing the first item in the list when I add the second, so there are now of the same item in the list. How do I add unique items to the list? Also, in the collection world, I could define a index of an item by placing the index value into second item of the Add Function.
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