How to store each individuals characters into a variable?

Hi,

I have to know how to split the characters from a string and store it in a separate variable?. The string used is "hello" . I want to store the characters h,e,l,l,o into a single array. For Example, the string "hello" is given through the textbox. I need to store it in a array named "a". (i.e) a[0]=h
a[1]=e
a[2]=l
a[3]=l
a[4]=o...If anyone knows please reply me.......   

 using an array list:

        Dim helloString As String = "hello"
        Dim holder As New ArrayList
        Dim x As New Char

        For Each x In helloString
            holder.Add(x)
        Next