Below the xml doc
<Root>
<Global>
</Global>
<local>
<section name="A">
<subsection name="A">
[Code] .....
Now I want the property1 whose section name="B" and subsection name="B" and innersection name="B" in one single query using linq to xml.
I have a VB.NET search routine, part of which is provided, below, that checks all Text cells in a DataGridView for a given string (inclusive), using a basic set of nested loops to perform the search:
' Search for the first occurrence of the given string
For Each row As DataGridViewRow In dgvMembers.Rows
' Skip the new row
[Code].....
is there a way to replicate this behavior using LINQ? Basically I would like the query to select (or return) the first DataGridViewCell whose text contains the search string. I've done some tinkering with sub-queries and the like, but I'm still having trouble wrapping my brain around the concepts (too many years of writing T-SQL, I guess).
I am creating a mediaplayer / playlist creator tool that basically imports MP3 songs into playlists (grids). I'm looking to add search functionality where the user can search all open playlists (or a subset of the open playlists). A Playlist is basically a collection of AudioFiles, where an AudioFile is a class that holds the filename of the MP3 file and then exposes the tags (Title, Artist, Album, etc) in public properties.
The idea is that the user can search for a certain expression (for example "the"), and that he can then choose whether to search in the title, in the title and artist, in the title or artist, in the title, artist and/or album, etc. However, I'm having a hard time implementing this and also having it kind of dynamic.
At the moment I am simply gathering all the AudioFiles from the open playlists (or from the subset of playlists the user chooses) and then running a simple LINQ query to find those AudioFiles where the Title contains the search text. Then I display the resulting AudioFiles in a new playlist window:
[Code]....
In case the AND / OR distinguishing is too hard, I would be happy to start with just letting it default to 'OR', so that the user can check Title and Album for example. If he would then search for 'a' then all songs that contain 'a' in their title as well as all songs that contain 'a' in their album should be returned. I guess that makes it easier, but I still wouldn't know how to dynamically create the LINQ query.
[Code]...
how to do this. kindly show me some sample code for this
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 my previous post I've ask how to add a new xml node..now that im knowlegable at that. but heres a followup question, how can I get the nodes' name and then tell vb to write a child node in that node?
Here my code:
Private Sub Button_Create_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button_Create.Click
Try
[Code].....
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 the following list
[Code]...
I am trying to remove the Car node with ID = 1000, but i can't get it right Here is my Code, note that the debugger never hits e.Remove:
[Code]...
I was writing a generic class to read RSS feed from various source and to consolidate in one collection of object in VB.net.
Basically the function - using LINQ to XML - is working properly, but I have a problem when the RSS feed I am trying to read does not contain one of the node (as you know, many of them are optional). I would the returned value to be an empty string or nothing, but instead I get a runtime error back. I searched the web for the same problem and I found this post [URL] that apparently explain a workaround, but it does not work with my code.
I am also surprised by the little resources I am finding about this issue, so I am now wondering if I am even putting the question in the right terms...
Following you can find the code:
Dim PostsEnum = From BlogPost In XMLSource.Descendants("item")
Order By DateTime.Parse(BlogPost.Element("pubDate").Value) Descending
Select New Post() With {
[Code].....
I 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]....
im querying the name of a movie in an xml file contained within the node "name" I have no problems getting the node but i cannot match the name to the node name because of character like : -
[Code]...
How do I work out what the namespace declaration is for the Extension node?I want to return all of the child nodes under: GPO->User->ExtensionData->Extension..[code]I get the following error: Sequence contains no elements..Also, the XML sample I have provided is only a small snippet, the ExtensionData->Extension nodes can be nested in different areas, so I was hoping to find the way of specifying the full path.
View 2 RepliesAfter being quite sick of the my.settings-file behavior, I started to create an XML-file (with unique values). Now this works great!!! All my settings, connectionstrings, etc are loaded from an external file and won't be overwritten by the app. itself. But I was wondering how do I save a value/setting? Simple example:
HTML
<test>
<country>Holland</country>
[code]....
read the XML and node:
vb.net
Dim readXML = Xelement.Load(Application.StartupPath & "XMLFile1.xml") ' check if the node isn't empty (crash) If readXML.Descendants("country2).Nodes.Count > 0 Then Textbox1.Text = readXML.Descendants("country2).Nodes(0).Tostring() Else
[code]....
Given the following XML, I would like to return all eventtitles where the eventtype id = 23. My current query only looks at the first eventtype, so returns the wrong result.
<event>
<eventtitle>Garrison Keillor</eventtitle>
<eventtypes>[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."
how can I search for a text in a tree view but by being able to tell from which level I want to start searching?
View 1 Replies[Code] my problem is if i search the class node with the name attribute of value "IT MAJEL 03", the xml reader reads through the first class which is "IT MAJEL 04" and read all of its child nodes(which i think is very awkward. why continue reading to its child nodes if the class name you're looking does not even match). is there another way to actually jump the reader of the xml node to the next xml node of the same level?
I mean if I search the class named "IT MAJEL 03", the reader should jump to the next same level element it does not match the query. It should skip reading the "IT Majel 04" child nodes. what I want to achieve here is I want to save nanoseconds of computing.
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 have built a database structure that represents a category tree to help classify some of the data we have stored. The implementation is that each record in the Category table has a nullable foreign key back into the Category table to represent the parent Category of this category (one-to-many), essentially allowing for subcategories within a broader parent level. There is a CategoryMembership table that links a record in the Item table to its respective Category (many-to-many). I have created the DBML for this database, and it has a member access structure that includes the following:
[Code]...
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"
<?xml version='1.0' encoding='utf-8' ?>
<All>
<Customers>
[code].....
I am trying to make a simple search method using sql to linq in visual studio. In my database, i have the fields "Firstname" and "Lastname", and my search string is "name". How can i make a simple linq query which searches both fields?
in plain SQL i would do something like this: "SELECT (Firstname + Lastname) as 'Fullname' FROM table WHERE Fullname LIKE '%searchstring%'
I have done edit and remove and create xml but there is one problem adding.
Public Sub Add()
Dim xLabResults = New XDocument()
xLabResults = XDocument.Load(frmMain.xLabResultXmlPath)
[code]....
It does add but there is unnecessary xmlns="" on the add node, and ofcourse error reading it thus ignored when I read the xml.
dp.SyntaxHighlighter.ClipboardSwf = '/dp.SyntaxHighlighter/Scripts/clipboard.swf'
dp.SyntaxHighlighter.HighlightAll('73c54fd0ff56414895293ae2ac3c2a3e')
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].....
