How To Search List By Index Or String

Aug 29, 2011

How on specific behaviour can be created in a custom class. I want to be able to create a custom class (a kind of list) where I can access the items by their index (this is the easy part), but also by a string that would describe them. Here is an example:
MyClass(1).SomeProperty = "NewValue"
MyClass("Item1").SomeProperty = "NewValue"

You can see this kind of behaviour in dataset for example where you can select a table by its name or by its index like this :
DataSet.Tables("MyTable").Rows...
DataSet.Tables(1).Rows...
How can I create a custom class that will behave like this?

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Search And Get Index String In A Big File?

May 22, 2011

How to search and get position a string in a big file?I have searched in forum2 and get several ways to search for strings in files, but it is not for large files above 500 mb,I have just been make a function to search string and get its index,but it is very slow and uses lots of RAM.This is my function

Function StringInFile(ByRef fs As FileStream, ByRef
substring As String, Optional ByVal occurence As Integer = 1,_
Optional ByVal start As Integer = 0, Optional ByVal count As Integer = -1) As Integer

[code]....

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Search For A String In An Array And Get Its Index?

Nov 6, 2010

Given an enum similar to this:

Friend Enum TestValue As Int32
tstNotSet = -1
tstA = 0

[code]....

As noted in my comment to Jon Skeet, this construct, along with the rest of the Object's components, executes 100,000 times in a profiling loop in ~570ms (rough average of 3-5 runs).

Exchanging the above construct out with a smaller Array.IndexOf construct loops 100,000 times in ~630ms (again, 3-5 runs, rough average, the whole Object). The new construct looks like this:

Dim p As Int32
p = Array.IndexOf(TestValues, s)
If p <> tstNotSet Then

[Code]....

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Search An Array Of Structs Using A String As An Index?

Apr 1, 2009

I have been searching for a while now, but I still can't seem to figure this out. I wrote a rather large program, and to make things more efficient I started to create structs to store more info in a variable.All was well replacing my old code with new code, till I reached a certain point and found that blindly using a loop of integers to access the indexes of the array wouldn't work anymore... I need to access a specific struct by the information contained in a single variable within the struct (like a hashtable key), but can't seem to figure out how.

Is it possible for me to go through my array indexes in a fashion like this?:
Dim myArray(TableCount) As myStruct
Dim TableName As String = "SomeTable"

[code].....

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Search The Index Of The First Value In A String Without Calling IndexOf.

Jun 30, 2009

i want index of the first value in a string Without calling IndexOf.

Like, " I am going" and my search value is "am"

so it should give me index value as "2".

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Sorting - Sort List(of String()) Using A Variable Index Into String() As Key ?

May 30, 2012

I have a List(of String()). I have written a custom comparer (implements IComparer(of string)) to do an alphanumeric sort.Is there a way to sort the List using a given index to determine which position in the String() to sort by? In other words one time I might sort by Index = 0 and another time by Index = 3. The length of all String() in the list is the same.For reference this question is similar to Sort List<String[]> except I am using VB.net and that question is hardwired to Index=0.

EDIT from OP's comments:I started simple with the non custom comparer but I am getting an error: expression does not produce a value. Not sure what I am doing wrong.Here is the code:

Public Shared Function SortListOfStringArray(ByVal ListOfStringArray As List(Of String()), ByVal SortByIndex As Integer) As List(Of String())
Return ListOfStringArray.Sort(Function(x, y) x(SortByIndex).CompareTo(y(SortByIndex)))
End Function

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Find Index In List(of String)

Jun 7, 2010

I have an List(of String), i need to find the index of a particular string in that list. I have searched msdn , but i am confused over the predicate methods. I have never used predicates. This i what i have tried

vb
'on button1 click
Dim Heads As List(Of String) = Me.GetSelectedNodes()
Dim tmp As Integer

[Code].....

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.net - Search A Strongly Typed List For A String?

Mar 14, 2012

How can I "search" through a strongly typed list for a string?

I am attempting .Contains(TheString), however it errors stating Unable to cast object of type 'System.String' to type 'o7thCrawler.Typing.ImportantTyping'

Here is the code:

Public Class LinkTyping
Public Property Url As String
Public Property Title As String

[Code]....

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LINQ To SQL Basic Column Search Doing OR / AND Of A List<string>?

Nov 23, 2011

Is there a way to check if a column contains all or any of an items in a list? Example "ABCDEFG" is my column value. "A" "C" "L" is my list stored in a list. I need to find rows that contains at least one item in my list. Then items that contains ALL the items in my list (a basic OR / AND search such as a SE would have)

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Determining The Index Of A List Based On Another List And Vice Versa?

Jan 6, 2012

Suppose you have list 1 (ilist1) and list 2 (ilist2) both lists have 3 items.

At index 0 item1 which has text "-- Select --"
At index 1 item2 which has text "Yes"
At index 2 item3 which has text "No"

Both lists have identical items. I would like to know if it is possible to have the selection of list one be "Yes" and the selection of list two be "No" and vice versa using SelectedIndexChanged or something of the sort.

For example:
ilist1 = --Select--
ilist2 = --Select--

[Code]....

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.net - Function To Accept List(Of String), Array & String And Similarly Return List(Of String)?

Jul 29, 2011

I want the Function to accept List(Of String), Array & String and similarly return List(Of String), Array & String respectively. The Function simply adds a string (month) to the input collection. I just want to use it for string, array and list with needing to think of conversions.

[Code]...

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C# - Add A Location To Windows 7 Search Index?

Sep 9, 2011

Is there any way by which I can add a location to Windows 7 search index and make it indexed in .Net?

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Index Search Of Parallel Arrays?

Feb 3, 2010

getting started with creating an index search for parallel arrays. When the user enters the specific "code", and presses enter, the information in the other arrays should be displayed based on its matching index. I'm pretty sure I use "For i = " but I'm lost. I have my arrays set up like this:

Dim code(9) As String
code(0) = "A"
code(1) = "H"

[code]....

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Use The Indexof Method To Search For An Index A Number?

May 1, 2011

How do I use the Indexof Method to search for an Index a number? The number will be different on each line of the file. Each array has a name and a different zip code. I want to tell it to search for the first number in the line. Everything before that index will be first name, last name, and then zip code.

[Code]...

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Index Of Search - Display First Result Of Text Find

Oct 30, 2011

I have the following code:
indexOfSearchText = TextBox1.Find(item, start, TextBox1.TextLength, RichTextBoxFinds.WholeWord)
If indexOfSearchText <> -1 Then
startindex = indexOfSearchText
End If
But I want just the first result, if I have an example text:
then it searches twice "is", I just want the first "is".

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VS 2008 Search Item A (from A List Of X Items) In List B?

May 5, 2010

i want to search item A (from a list of X items) in list B but i want to get the item not found example Search ITEM A in LIST B if not found then return a print....if found continue with ITEM B..and so on.

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2010 DataView.Find() Query - Search On A Index / Row Number

Nov 15, 2011

I am trying to do a search on a index/row number taken from a dataview i.e. I enter 379437 in the input box which I know has a index/row number of 6. Now when I replace the Rows(index) with a Rows(6) I get the results that I want. When I run the code below the index comes out as 75 which displays the first row from the dataset which is a completely different set of results.

[Code]...

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Highlight Listview Item From Mysql Search Statement Then Get The Index?

Feb 15, 2012

highlight listview item from mysql search statement then get the index?

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Index - Create A Telephone Directory With Search Option(textbox)

Mar 29, 2010

I need to create a telephone directory with search option(textbox). I use sql db as backend and vb.net for frontend. In this the user must search for a particular name using the textbox and the results have to be displayed in the gridview. how to do this?

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C# - With LINQ, How To Transfer A List<List<string>> To List<string>

Dec 15, 2010

I got an object of List<List<string>>I need to bring this into a ist<string>I have no idea how to do this with LINQ.

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A List Where An Index Has Three Values Associated With It?

Nov 16, 2011

I have been searching everywhere but I am unable to find a reference to what I need.I have a huge number of entries where each entry is composed of three long numbers:

a b c
1 2 40
2 1 40
1 8 12
3 9 13
8 1 12
ect.

in my algorithm I will find that I need to disregard values in column a which will then lead me to disregard values in column b. I initially thought that I may want to use three arrays and just change the disregarded value to a null value with each iteration. find function that would allow me to not have to loop through the entire array every time.This lead me to want to define the columns as lists where I could remove specific values from the list and reduce the size of the list with each iteration of the algorithm. The problem then is how do I say, listb.remove(8) and at the same time have the corresponding values for lista(1) and listc(12) removed?

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Get The Selected Index Of The List Box?

Dec 9, 2010

'Get the selected index of the list box 'use that selectedindex for the row of the array and get both the quantity and price into local variables in VB

[Code]...

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List Box Selected Index?

Dec 6, 2011

I think I'm having a brain fart on this but I can't seem to figure out why this is not working.

Public Class Radio_Main
Dim RadioDial As String = 1
Dim Go As String = "http://"
Private Sub pb_Tuner_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles pb_Tuner.Click
'My.Computer.Audio.Stop()

[Code]...

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Find List Index For A Given Property Value?

Aug 15, 2011

Ive got two lists (each representing a table in a DB, so they are related). lstTransaction has t_id, date, and cust_id. lstCustomer has Name, and cust_id.For each item in lstTransaction Id like to find the index in lstCustomer where lstCustomer.cust_id = lstTransaction.cust_id.

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LINQ: Get Index Of XML Setting List(Of

Mar 21, 2012

I am trying to get an index of a List(Of Details) Details being a class i use instead of an annon method. Is it because i am using array.findindex when it's not an array but a list(Of???

Dim index As Integer = Array.FindIndex(Details, Details.FirstOrDefault(Function(nd) nd.Name = "name"))
Error1Data type(s) of the type parameter(s) in method 'Public Shared Function FindIndex(Of T)(array() As T, match As System.Predicate(Of T)) As Integer' cannot be inferred from these arguments. Specifying the data type(s) explicitly might correct this error.

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List (Of T) Items Accessed By Index Or By Name?

Oct 17, 2011

I want to build my own class. In it, I need to recreate a behavior we can see in DataTable and in some other places : accessing items by their name or by their index. [code]...

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List (of T) With Items Accessible By Name And Index

Oct 17, 2011

I want to build my own class. In it, I need to recreate a behavior we can see in DataTable and in some other places : accessing items by their name or by their index. How can I reproduce such a behavior. Here's what I mean :

'Here's one way to access the data
A = MyObj(0).value
'Here's the other way I would like to acces it
A = MyObj("Blablabla").value

How can I create my class so I can access items in an array (or list preferably) by it's index or an unique Name?

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List Of Integers Indexed By Key Or Index?

Jul 25, 2010

I would like to create a list of integers. The list will be items that I need to index by a key (string) or an index, which I set. For example I have items 1, 2, and 5. I would like to call Array(5) = 1. Where the the 5 is indexing a particular item 5, not the 5th item in the array. Using Array("5") = 1 could work as well. I tried using a List, but the only index is the ordered element of the list. I tried a Collection, but I kept getting errors that the items of the Collection are read only. How can I do this?

To be more specific, I have a simple game application which has a Player class. Each Player is trying to collect hits of say 3 fields {1,2,5}. I need to store how many times a player hits each of the 3 fields. So, I would like to read and write using logic like player(1).field(5) = 5. I want to add an object to the Player class which stores the number of times each of the 3 fields has been hit.

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List Or Array With A Text As Its Index?

Jan 24, 2011

Using vb.net, is it possible to have a list of values such as:

Green
Black
Blue

and the index to be a text value such as

Table
Desk
Chair

something like this

ListColors("Chair")="Green"
ListColors("Desk")="Blue"
ListColors("Table")="Black"

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List(Of T) Where Items Can Be Accessed By Index Or By Name

Oct 17, 2011

I want to build my own class. In it, I need to recreate a behavior we can see in DataTable and in some other places : accessing items by their name or by their index. How can I reproduce such a behavior. Here's what I mean :

[Code]....

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