[2005] findstring(IndexOf)

[VikingMan]

Hi is there any function that would return the indexOf all apples in this string :

string = orange apple apple orange grape grape apple orange

[VBDT]

I believe you need to writh a function to loop through the string and get the indexes.

[VikingMan]

I dont know how, that's why i need help..

[jmcilhinney]

It would be relatively inefficient but Regex.Matches would do the job in one go. I'd be inclined to write a method call IndexOf repeatedly and return the results in a single array or collection and then call that method as needed.

[VBDT]

this is very simple stuf so you should do it your self.

Private Function GetIndexs(ByVal str As String, ByVal exp As String) As Integer()
        Dim indexes As New List(Of Integer)
        Dim helper, index As Integer
        While str <> "" AndAlso helper <> -1
            helper = str.Substring(index).IndexOf(exp)
            If helper <> -1 Then
                index = helper + index
                indexes.Add(index)
                If index + 1 < str.Length - 1 Then
                    index += 1
                End If
            End If
        End While
        Return indexes.ToArray
    End Function

[jmcilhinney]

IndexOf is overloaded:

Private Function IndexesOf(ByVal str As String, ByVal substr As String) As Integer()
    Dim indexes As New List(Of Integer)
    Dim index As Integer = 0
 
    While index < str.Length
        index = str.IndexOf(substr, index)
 
        If index = -1 Then
            Exit While
        End If
 
        indexes.Add(index)
        index += 1
    End While
 
    Return indexes.ToArray()
End Function

[VBDT]

Yes that defiantly looks cleaner.

[VikingMan]

this is great, thank you very much