I have tried a couple different ways and cannot seem to get the result I want using vb.net.
I have an array of strings. {"55555 ","44444", " "}
I need an array of integers {55555,44444}
This is a wpf page that is sending the array as a parameter to a crystal report.
Any help is appreciated.
You can use the List(Of T).ConvertAll method:
Dim stringList = {"123", "456", "789"}.ToList
Dim intList = stringList.ConvertAll(Function(str) Int32.Parse(str))
or with the delegate
Dim intList = stringList.ConvertAll(AddressOf Int32.Parse)
If you only want to use Arrays, you can use the Array.ConvertAll method:
Dim stringArray = {"123", "456", "789"}
Dim intArray = Array.ConvertAll(stringArray, Function(str) Int32.Parse(str))
Oh, i've missed the empty string in your sample data. Then you need to check this:
Dim value As Int32
Dim intArray = (From str In stringArray
Let isInt = Int32.TryParse(str, value)
Where isInt
Select Int32.Parse(str)).ToArray
By the way, here's the same in method syntax, ugly as always in VB.NET:
Dim intArray = Array.ConvertAll(stringArray,
Function(str) New With {
.IsInt = Int32.TryParse(str, value),
.Value = value
}).Where(Function(result) result.IsInt).
Select(Function(result) result.Value).ToArray
Dim tempInt% : Dim intA As Int32() = intStrA.Where(Function(x) Int32.TryParse(x, tempInt)).Select(Function(x) tempInt).ToArray()
stringList.ConvertAll(AddressOf Int32.Parse) looks the cleaner solution to meYou can use the Array.ConvertAll method:
Dim arrStrings() As String = {"55555", "44444"}
Dim arrIntegers() As Integer = Array.ConvertAll(arrStrings, New Converter(Of String, Integer)(AddressOf ConvertToInteger))
Public Function ConvertToInteger(ByVal input As String) As Integer
Dim output As Integer = 0
Integer.TryParse(input, output)
Return output
End Function
Maybe something like this:
dim ls as new List(of string)()
ls.Add("55555")
ls.Add("44444")
ls.Add(" ")
Dim temp as integer
Dim ls2 as List(Of integer)=ls.Where(function(x) integer.TryParse(x,temp)).Select(function(x) temp).ToList()
ToArray instead of ToList.Maybe a few more lines of code than the other answers but...
'Example assumes the numbers you are working with are all Integers.
Dim arrNumeric() As Integer
For Each strItemInArray In YourArrayName
If IsNumeric(strItemInArray) Then
If arrNumeric Is Nothing Then
ReDim arrNumeric(0)
arrNumeric(0) = CInt(strItemInArray)
Else
ReDim Preserve arrNumeric(arrNumeric.Length)
arrNumeric(arrNumeric.Length - 1) = CInt(strItemInArray)
End If
End If
Next
CINT will throw an OverflowException if the value is numeric but out of the range of an integer, because IsNumeric returns also true for values that are in decimal range. The same is true if the value contains a . since this could be converted to a Double.
My $.02
Dim stringList() As String = New String() {"", "123", "456", "789", "a"}
Dim intList() As Integer
intList = (From str As String In stringList
Where Integer.TryParse(str, Nothing)
Select (Integer.Parse(str))).ToArray
Everything is much easier ))
Dim NewIntArray = YouStringArray.Select(Function(x) CInt(x)).ToArray
