Char combine

In many VB.NET programs, we may have some Char values we want to convert into a single String. We can combine these Chars into a String in a variety of ways.

By creating a Char array, we can place each Char in an element of the array. Then we can convert the array to a String with the String constructor.

Example

We introduce a function called CharCombine in this VB.NET module. CharCombine contains the logic for combining 4 Chars into a String. Any number of Chars could be combined.

Module Module1
    Function CharCombine(c1 as Char, c2 as Char, c3 as Char, c4 as Char) as String
        ' Create array by specifying last valid index as size.
        Dim result(3) as Char
        result(0) = c1
        result(1) = c2
        result(2) = c3
        result(3) = c4
        Return New String(result)
    End Function

    Sub Main()
        ' Part 1: use function to combine 4 Chars into a string.
        Dim c1 as Char = "a"c
        Dim c2 as Char = "b"c
        Dim c3 as Char = "c"c
        Dim c4 as Char = "d"c
        Dim resultFromFunction = CharCombine(c1, c2, c3, c4)
        Console.WriteLine("FUNCTION RESULT: [{0}]", resultFromFunction)

        ' Part 2: place code inline to convert from 2 chars to a string.
        Dim result(1) as Char
        result(0) = "x"c
        result(1) = "y"c
        Dim resultString = New String(result)
        Console.WriteLine("RESULT: [{0}]", resultString)

        ' Part 3: use calls to ToString and concatenate them.
        Dim resultSlow = c1.ToString() + c2.ToString() + c3.ToString()
        Console.WriteLine("TOSTRING: [{0}]", resultSlow)
    End Sub
End Module
FUNCTION RESULT: [abcd]
RESULT: [xy]
TOSTRING: [abc]

For situations where performance does not matter, calling ToString on each Char and then using "+" to concat the strings is acceptable. But this code involves another layer of conversion.

For converting Chars into Strings, we can use a Char array and then the String constructor. This works for any number of Chars—and we can even use For-loops to fill the Char array.