I want to statically define a mapped array of strings like:
var dict = {cat:50, bat:10, rat:30};
and lookup values within it like:
MessageBox.Show( dict["cat"] )
views:
98answers:
2
+5
A:
Dim dict As New Dictionary(Of String, Integer)()
With dict
.Add("Cat", 50)
.Add("Bat", 10)
.Add("Rat", 30)
End With
smoore
2010-03-03 19:56:54
`As New Dictionary`? or has VB changed since last I used?
dotjoe
2010-03-03 19:59:16
+1 Beat me to it - but needs the "As New"
Kyle Rozendo
2010-03-03 19:59:28
Is this the only way? Doesn't VB have built-in support for keyed arrays?
Jenko
2010-03-03 20:01:08
@dotjoe and kyle: Indeed I do, good catch
smoore
2010-03-03 20:02:18
@dotjoe,Kyle,smoore: it is just the short way of doing:Dim dict As Dictionary(Of String, Integer) = New Dictionary(Of String, Integer)()which is a shorthand version of:Dim dict As Dictionary(Of String, Integer)dict = New Dictionary(Of String, Integer)()It is possible to use the shortest version due to this scenario being a "special" case: the variable is assigned with a value immediately upon decleration, the assigned value is newly created, and the variable's type is identical to the value's type.
M.A. Hanin
2010-03-03 21:26:22
cool SO now recognizes the @username comment replies in your recent responses. lol at Hanin...I think you missed the part where `New` was missing from the answer.
dotjoe
2010-03-04 01:09:50
@dotjoe, I sure did! Thought you guys are new to the New keyword :-)
M.A. Hanin
2010-03-04 06:29:19
+4
A:
In .NET 4.0:
Dim d As Dictionary(Of String, Integer) From
{{"cat", 50}, {"bat", 10}, {"rat",30 }}
Robert Harvey
2010-03-03 20:09:54
This is supposed to be the preferred way of doing Collection Initialization now
masenkablast
2010-03-03 20:14:37
VB.NET reports "Array initializers are only valid for arrays".. Have you actually tested this code?
Jenko
2010-03-03 20:15:20
I'm trying to figure out if this code is specific to .NET 4.0. The syntax is slightly different there.
Robert Harvey
2010-03-03 20:17:01
Whup. This is speculative syntax, see here: http://www.panopticoncentral.net/archive/2008/05/05/23212.aspx. It does exist in .NET 4.0, however (under slightly different syntax). See here: http://msdn.microsoft.com/en-us/library/dd293617(VS.100).aspx
Robert Harvey
2010-03-03 20:20:01