evaluating the contents of a string

[echo_rev]

My app takes in a string from a text box which is of course located on a form.

The contents of the string will be some form of expression statement

EG (A*B)+(C/D)

Once the user has entered their expression into the textbox and pressed a control button I want to be able to go though the string and split the contents into chars, oprators(*,+,-,/) and the parentheses.

Is split the best way to do this? Ive been playing around with it and can't seem to find a way of picking out all chars (I could by divining a list of chars but that would take forever)


Any ideas

[nemaroller]

So using the example expression you gave:

You want....
'EGABCD'
'()()'
'*+/'


?

[echo_rev]

yes that is correct

[nemaroller]

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim s As String = TextBox1.Text
        Dim characters As New System.Text.StringBuilder(15)
        Dim paranthesis As New System.Text.StringBuilder(10)
        Dim operators As New System.Text.StringBuilder(10)
        Dim c As Char
        For i As Integer = 0 To s.Length - 1
            c = s.Chars(i)
            If Char.IsLetterOrDigit(c) Then characters.Append(c)
            If Char.IsPunctuation(c) Then
                If Not (c = "(" Or c = ")") Then
                    operators.Append(c)
                Else
                    paranthesis.Append(c)
                End If
            End If
            If Char.IsSymbol(c) Then operators.Append(c)
        Next
 
        Debug.WriteLine("characters: " & characters.ToString)
        Debug.WriteLine(Environment.NewLine)
        Debug.WriteLine("paranthesis: " & paranthesis.ToString)
        Debug.WriteLine(Environment.NewLine)
        Debug.WriteLine("operators: " & operators.ToString)
 
    End Sub

[echo_rev]

that is wicked - It never crossed my mind to use the char classes methods! thanks for the point in the right direction !-)