I need to find next highest no in a field that is a stick ref it has chars at front and 0 padded How so I strip off front chars and 0's to get actual highest no number in the table field?Am using LINQ against entity framework?
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I'd like to know how to sort an array that has entries with numbers after text.
I have a list of four entries:
Book 1
Book 2
Book 11
Book 12
Using Array.Sort(aBooks) returns
Book 1
Book 11
Book 12
Book 2
Is there a way to have it sort lowest to highest like 1 2 11 12 instead of 1 11 12 2?
i have a column that i want to select from a table called style_number
each entry is listed as "something-stylenumber"
is there a way to strip everything from the - and to the left from the string when it is returned from mysql?
SELECT style_number FROM table1
I do not want to have to use vb.net to edit the returned string for each line that is pulled
When a WebBrowser controls loads and navigates to a page it strips out everything after the '?'
how to overcome this and pass the query string to the page?
I am trying to write some Linq to SQL that will bring me back a list of rows containing a single instance of BaseQuestionIDs but I want the row with the highest version, so, from the following table of data:
Id CreatedDate Version BaseQuestionID
2 2009-10-07 13:47:27.687 1 2
3 2009-10-07 13:49:35.010 1 3
4 2009-10-09 16:03:45.973 1 5
[code]...
I want to return:
Id CreatedDate Version BaseQuestionID
2 2009-10-07 13:47:27.687 1 2
3 2009-10-07 13:49:35.010 1 3
[code]...
I have tried a variety of things, but have not nailed it yet. I am working in vb.net?
I solved this issue in this thread but there still are issues with special chars. ie 'I thought by doing parameters that it would take care of any special chars for you. Well i am still getting mysql exceptions about syntax. I look at the string it is working with and it has a "'" in it.Why are they not working as I expect them to?
View 7 RepliesI don't know if I worded this properly, but I have a mdb query that I display in a Datagrid on my form. The first column is TransactionNumber, which is the primary key and a running total (ex. RackingTransactionKey=RackingTransactionKey + 1). What I need to do is when the form is opened, find the highest (last) TransactionNumber from the query or Datagrid and assign it to a variable (RackingTransactionKey), so I can can update it (+1), therefore generating a unique number so I can add data to the query.
[Code]...
I know that LINQ queries are deferred and only executed when the query is enumerated, but I'm having trouble figuring out exactly when that happens.Certainly in a For Each loop, the query would be enumerated.What's the rule of thumb to follow? I don't want to accidentally enumerate over my query twice if it's a huge result.
For example, does System.Linq.Enumerable.First enumerate over the whole query? I ask for performance reasons. I want to pass a LINQ result set to an ASP.NET MVC view, and I also want to pass the First element separately. Enumerating over the results twice would be painful.It would be great to turn on some kind of flag that alerts me each time a LINQ query is enumerated. That way I could catch scenarios when I accidentally enumerate twice.
In VB.net I've got the following line that removes all non-alphanumeric chars from a string:
return Regex.Replace(build, "[W]", "")
I now need to extend this to remove non-alphanumeric chars that aren't [] or _. I've changed the line to:
return Regex.Replace(build, "[W[]_]", "")
However I'm pretty sure that this says
replace non-word or [ or ] or _
how do I negate the tests for the [] and _ chars so that it says
replace non-word and not [ and not ] and not _
Some examples:
"[Foo Bar_123456]" => "[FooBar_123456]"
"[Foo Bar_123-456*]" => "[FooBar_123456]"
How to convert or make a cast of a List object typized as a container of chars like
Dim mylist As List(Of Char) = New List(Of Char)(New Char() {"1"c, "2"c})
in a simple array of chars as
Dim mychars() As Char
without make a loop for...
given this function:
Public Function Search(ByVal StartIndex As Integer, _
ByVal MaxResults As Integer, _
ByVal AccountNumber As String, _
ByVal LastName As String, _
[Code]....
instead of what I expected:
Select count(*) from remitline where lastname = "smith"
What am I doing wrong building up the where clause? I'm using Castle ActiveRecord 2.1
if there is that much of a performance gain in running a LINQ stored procedure versus a LINQ query?
View 1 RepliesI have to join two main tables, and I need to filter the results by elements in an ASP.NET web form. These filters are created on the fly so I have to use a lot of where extensions to filter the query. I want to execute the query with as optimized SQL as possible.
I am first doing a simple join between TW_Sites and TW_Investigators. Then there are two sub-tables that are involved. TW_InvestigatorToArea and TW_InvestigatorToDisease. While most of the where clauses are working fine, I have found a performance issue that won't be an issue right now, but will be an issue as the table gets bigger.
The arrays DiseaseCategories and DiseaseAreas would be the results of a CheckBoxList result.
Protected Sub LoadResults()
'Get Dictionary of Filters
Dim FilterDictionary As OrderedDictionary = Session.Item("InvestigatorFilterDictionary")
' Initialize LinqToSql
[code]....
Forgive my ignorance on this.I have this LINQ Query:Dim ngBikersDataContext As New CarBikeWalkDataContext
bikersList = (From c In ngBikersDataContext.Reg_Bikers _
Order By c.L_Name _
Select New Bikers() With { _
.BikerID = c.BikerID, _
.F_Name = c.F_Name, _
[Code]...
with the error "Overload resolution failed because no accesible 'Select' accepts this number of arguments."
Over the "NEW" I get an error " ')'expected."
We are doing a query against an in-memory collection of LINQ data objects. The wrinkle is that we are ordering by a column in a related table whose records have not necessarily been loaded yet (deferred loading:)
Dim oPkgProducts = _
From b In oBillPkg.BillProducts _
Where b.Successful.GetValueOrDefault(Common.X_INDETERMINATE) = _
[code]....
How do I add ROW_NUMBER to a LINQ query or Entity? How can I convert this solution to VB.NET?
[Code]...
I'm having trouble porting that last line. I have been unable to locate a VB.NET example. I'm actually not looking for any paging functionality like the example provides, just good old-fashioned Row_Number(Order By X) row index.
I was wandering is it possible to use a query within another query below is the code I am trying to use.
Public Function GetInventByComp(ByVal CompID As String) Using DC As New DataClassDataContext
'need to get company id's based off names? thats bad should be name from Id need to rethink this
Dim invent = (From C In DC.Inventors_Companies _
Where C.CompID = CompID _
Select C.InventorID).ToString
[Code]...
I was trying to us multiple values in a string like "1, 3, 5" but I can't seem to get that working either so I am trying to use just a single value now. Can anyone help me? "Yes I am new to this"
I've been reading a fair bit about the performance of using LINQ rather than using a for each loop and from what I understand using a LINQ query would be a little bit slower but generally worth it for convenience and expressiveness. However I am a bit confused about how much slower it is if you were to use the results of the query in a for loop.
Let's say that I have a set called 'Locations' and a set of objects called 'Items'. Each 'item' can only belong to one 'location'. I want to link items that are under the same location to each other. If I were to do this using a normal 'For Each' loop it would be something like this:
For Each it as Item in Items
If it.Location.equals(Me.Location)
Me.LinkedItems.Add(it)
End If
Next
However if i was to use LINQ it would instead be this:
For Each it as Item in Items.Where(Function(i) i.Location.equals(Me.Location))
Me.LinkedItems.Add(it)
Next
is the second (LINQ) option going to loop once through the entire 'Items' set to complete the query, then loop through the results to add them to the list, resulting in essentially two loops, or will it do the one loop like the first (For Each) option?
Is it possible to do the following? [code] Basically I have one Load_Gridview function that is called on all postbacks, and rather than creating a bunch of different cases.I want the filters to stack.My actual code has more filters set up (4 or 5 of the).It all compiles ok but when I run and try to execute with active checked, or a department selected I get the following error. [code]
View 4 RepliesI have below XML file
<?
xml version="1.0" encoding="utf-8" ?><
PageFlow>
<
attributegroup name="Search"><
attributes>
[Code]...
I am looking to sum the "Status" field.
Dim _detailRecords As New DataTable
_detailRecords.Columns.Add("y")
_detailRecords.Columns.Add("z")
[Code]....
I'm also wanting to keep this as an IEnumerable of DataRow because I will be creating a datatable from it with
Dim yyyyy As DataTable = query8.CopyToDataTable
I am Fairly new to Linq and I am trying to write a simple query to return the error messages within my xml file.
<?xml version="1.0" encoding="utf-8"?>
<Error xmlns="urn:xxxxx">
The following errors were detected:
[code].....
I have a .Net 4 web app that uses Windows authentication and all works well however there is one trivial bug that is driving me nuts!
Visual Studio puts together the following for displaying who is logged in
<LoggedInTemplate>
Welcome <span class="bold"><asp:LoginName ID="HeadLoginName" runat="server" /></span>!
[Code]....
The problem is though that this is displaying as <domain>/user rather than just the username which I am assuming it is pulling this value from
System.Threading.Thread.CurrentPrincipal.Identity.Name
However I can't see anyway programtically to amend this?
So, I'm currently working on sending and receiving data via a serial port. In order to use readline, I need to send vbCrLf, which is fine. I'm trying to get it to display just the characters sent and not the additional characters like Cr and Lf. Here's the most basic part of my
SerialPort1.Write(HexSendBox.Text & vbCrLf)
ReceiveBox.Items.Add("Received: " & SerialPort1.ReadLine())
The data I will receive in the ReceiveBox if I seng 'GG' is:
[code].....
I am currently working on a project in where when a Coordinators ID is selected from a combo box, I need to strip an XML file and place the subject code and name in a list box. ("code" - "Name" - "Department number"). The xml file is written as follows. The main problem I am having is the fact the coordinatorsID is after the subect code, I have never dealt with this before.
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<start xmlns:xsi="[URL]">
<subject><SubjCode>AV597</SubjCode>
<SubjectName>VEHICLE AERODYNAMICS</SubjectName>
<DeptNum>116</DeptNum>
[Code] .....
if I run this under c#
from p in Addresses where p.Address2 == null select p.AddressID
it generate this query
SELECT [t0].[AddressID]
FROM [dbo].[Address] AS [t0]
WHERE [t0].[Address2] IS NULL
if I run this under vb.net
from p in Addresses where p.Address2 = nothing select p.AddressID
it generate this query
SELECT [t0].[AddressID]
FROM [dbo].[Address] AS [t0]
WHERE [t0].[Address2] = ''
p.Address2 is a varchar field that accept null value
why vb.net is "wrong" ?
I'm converting the Linq query below from C# to VB.Net. Can you spot my error? The query joins 3 XML datasets. C# - This one works great.
List<Course> courses =
(from course in CourseXML.Descendants(ns + "row")
join coursecategory in CourseCategoryXML.Descendants("Table") on (string)course.Attribute("code") equals (string)coursecategory.Element("DATA")
[code]....
I have been trying the following but it returns unexpected results:
Dim xd As XDocument = _
<?xml version="1.0" encoding="utf-8"?>
<root>
[code].....
The above result returns both 'element' nodes however it should only return the first where element/subelement@id=1/subsubelement@id=3 However if results.Ancestors. is used it returns the correct 'subelement' and if that line is not included it returns a single 'subsubelement' whih is also correct I don't understand why when mvoing to the 'element' it returns both (I realise both have a subelement with id=1 but I thought each further query would filter out the presvious results)?
I have a List of Price Objects (Price contains Date, High, Low) and am trying to extract monthly averages via LINQ. I have this working in C# but we have a few legacy applications that need it in VB.Net and I can't quite seem to figure out the conversion. I've even tried breaking it into two queries to no avail.
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Ok im trying to do a if statement in Linq and was wondering if it was possible to do something like:
Dim loadFriends = From p In db.UserRelationships Where p.aspnet_User.UserName = User.Identity.Name _
Or p.aspnet_User1.UserName = User.Identity.Name And p.Type = 1 _
Select New With {if p.aspnet_user1.user = "a certan username" then .username = _
p.aspnet_user.username else .username = p.aspnet_user1.Username}
[Code]...
