RESOLVED - is string a valid color ?

[illskills]

im stuck can anyone help me out there has to be a better way to determin if a string is or is not a colour ....

this is what i've found but im not using it ....

Dim mycc As New ColorConverter

  Try
                Dim lbl As New Label
                lbl.BackColor = mycc.ConvertFrom($STRING)
                IsColour = True
            Catch ex As Exception
                IsColour = False
                Return True
            End Try

[cicatrix]

Function IsColor(ByVal TextName As String) As Boolean
    If [Enum].GetNames(GetType(KnownColor)).Contains(TextName) Then Return True Else Return False
End Function

[illskills]

wow thanks that's awesome !

going to test it now

[illskills]

if the string format is in RGB will this still work ?

[cicatrix]

No, this was meant for

If IsColor("AliceBlue") Then ...

[illskills]

No, this was meant for IsColor("AliceBlue") Then ...

is there an easy way to check rather than breaking the string down ?

[cicatrix]

I'm afraid, no.

Function ColorFromRGBString(ByVal RGBString As String) As Color
        ' Input argument RGBString must be in "R, G, B" format, 
        ' for example "215, 188, 212"
        Dim rgbelems() As String = RGBString.Split(New Char() {","c})
        If rgbelems.Count <> 3 Then
            Throw New ArgumentException("Wrong argument " + RGBString)
            Return Nothing
        End If
 
        Dim components(2) As Byte, x As Integer
        For x = 0 To 2
            If Not Byte.TryParse(rgbelems(x), components(x)) Then
                Throw New ArgumentException("Wrong argument " + RGBString)
                Return Nothing
            End If
        Next
 
        Dim c As Color = Color.FromArgb(255, components(0), components(1), components(2))
        Return c
End Function

[illskills]

thanks cicatrix these are both very useful

i think i found an easy way ...

the string i have is either a file path or rgb value

since ","'s are not allowed in file paths im using the following check ...

if instr($string,",") > 0 then iscolour = true

but will put the above functions in my code bank

thanks
again
John

[cicatrix]

Your methods can lead to errors since you don't check what's in it.
For example, if I pass "A, B, C, D" to it it will return IsColor = True

Besides, you can create directories and filenames containing commas.

Check it yourself, in the command prompt type:

MkDir "C:\A,B,C"
echo test > "A,B,C.txt"

[illskills]

your right i just checked ... i thought ","'s were not allowed in file names ... but they are

.... the second function you posted is excellent im currently looking @ it now

[illskills]

    Function ColorFromRGBString(ByVal RGBString As String) As Object
        ' Input argument RGBString must be in "R, G, B" format,
        ' for example "215, 188, 212"

        Dim rgbelems() As String = RGBString.Split(New Char() {","c})
        If rgbelems.GetLength(0) <> 3 Then
            'Throw New ArgumentException("Wrong argument " + RGBString)
            Return Nothing
        End If
        Dim components(2) As Byte, x As Integer
        For x = 0 To 2
            If Not Byte.TryParse(rgbelems(x), components(x)) Then
                'Throw New ArgumentException("Wrong argument " + RGBString)
                Return Nothing
            End If
        Next
        Dim c As Color = Color.FromArgb(255, components(0), components(1), components(2))
        Return c
    End Function

i edited the code above ... the .count function wouldnt work on rgbemlems

so i replaced it with .GetLength(0) <> 3

is this correct ?

took out the argument exceptions and changed the return type to object

now it returns a color object if the string is a color and nothing if its not.

Dim c
            c = ColorFromRGBString($string)
            If IsNothing(c) Then
                Exit Function
            End If

[cicatrix]

is this correct ?

As long as it works...

[illskills]

As long as it works...

yes it seems to be working now

thanks for your help