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I am new to VB.net, usually a Python or Matlab programmer.I have begun programming in VB.Net. I am battling to reference an index of a string in an array without looping through a for loop

How can I find an entry in an array in one line? My thinking is this..

Dim indx As Integer
Dim MyArray() As String   

indx = MyArray.find("ThisEntry")

or the index of 

indx = MyArray.indexof("ThisEntry")

So far all I have found is function describing a method directly after you declare the variable? Am I missing something? or does the logic not make sense?

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    There is always going to be a loop somewhere, its just a matter of whether you call it or offload the capability to another function or method. Commented May 23, 2013 at 12:08
  • 1
    What do you mean by "So far all I have found is function describing a method directly after you declare the variable" sorry but I can't parse that statement, could you clarify it? Commented May 23, 2013 at 12:09
  • 1
    stackoverflow.com/questions/1764970/… Commented May 23, 2013 at 12:09
  • @YaugenVlasau: That's C#, not VB .NET Commented May 23, 2013 at 12:11

4 Answers 4

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Do it this way, after you have some content on your array, that now is empty:

Dim result As String = Array.Find(MyArray, Function(s) s = "ThisEntry")

To get the index:

Dim index As Integer = Array.FindIndex(MyArray, Function(s) s = "ThisEntry")
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5 Comments

@CarlosLanderas Maybe Extension methods are not really suitable for a beginner...
Yeah I prefer a thousand times C# style but....
+1 for Array.FindIndex.
Where is the +1? @Neolisk :P :P
@CarlosLanderas: Sorry, got distracted by something else. Fixed.
7

IndexOf works, you're just not using it correctly.

Dim arr As String() = {"aa", "bb", "cc"}

index = Array.IndexOf(arr, "bb")
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Dim MyArray() As String = {"a", "ThisEntry", "b"}
Dim indx As Integer = MyArray.ToList().IndexOf("ThisEntry")
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1 Comment

.ToList() creates a copy of the array which is a bit inefficient.
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Sub Main()
    Dim numbers As String() = {"aaa", "bbb", "ccc"}

    Console.WriteLine(numbers.ToList().FindIndex(Function(x) x = "bbb"))
End Sub
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1 Comment

Where are you passing "what" variable to findbbb function?

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