URL encode data RFC-3986 in vb.net

Question

How do I convert this code to VB?

/// <summary>
/// Returns URL encoded version of input data according to RFC-3986
/// </summary>
/// <param name="data">String to be URL-encoded</param>
/// <returns>URL encoded version of input data</returns>
public static string UrlEncode(string data)
{
    StringBuilder encoded = new StringBuilder();
    foreach (char symbol in Encoding.UTF8.GetBytes(data))
    {
        if (ValidUrlCharacters.IndexOf(symbol) != -1)
        {
            encoded.Append(symbol);
        }
        else
        {
            encoded.Append("%").Append(string.Format(CultureInfo.InvariantCulture, "{0:X2}", (int)symbol));
        }
    }
    return encoded.ToString();
}

I have tried a code converter but it errors with

Error BC32007 'Byte' values cannot be converted to 'Char'. Use 'Microsoft.VisualBasic.ChrW' to interpret a numeric value as a Unicode character or first convert it to 'String' to produce a digit.

Thanks In Advance

Answer 1

A converter you may used is not a programmer with deep knowledge of possibilities. It just a shallow mapper of keywords and syntax. It gave you the following line, right?

For Each symbol As Char In Encoding.UTF8.GetBytes(data)

This resulted in the error you mentioned. @jmcilhinney already gave you the correct answer (aka how a programmer would do it) which is actually a workaround, because to program this code correctly avoids using GetBytes() result as a Char enumerable.

But here is an other solution which solves the exact error message instead. In cases the situation not avoidable you may use this.

...
Imports System.Text
Imports System.Globalization
Imports Microsoft.VisualBasic
...

Public Shared Function UrlEncode(ByVal data As String) As String
   Dim encoded As StringBuilder = New StringBuilder()

   ' you get Bytes here...
   For Each dataByte As Byte In Encoding.UTF8.GetBytes(data)
            
      ' ... and convert to Char here
      Dim symbol = ChrW(dataByte)

      If ValidUrlCharacters.IndexOf(symbol) <> -1 Then
         encoded.Append(symbol)
      Else
         encoded.Append("%").Append(String.Format(CultureInfo.InvariantCulture, "{0:X2}", Microsoft.VisualBasic.AscW(symbol)))
      End If
   Next

   Return encoded.ToString()
End Function

EDIT:

P.S.: Why are you using CultureInfo.Invariant in string to hex format at all? What difference will it make? The following seems to be enough:

encoded.Append("%").Append(Microsoft.VisualBasic.AscW(symbol).ToString("X2"))

EDIT2:

As @Heinzi pointed out @jmcilhinney's answer isn't correct. Use mine! :)