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How do I get the color from a hexadecimal color code using .NET?

How can I get a color from a hexadecimal color code (e.g. #FFDFD991)?

I am reading a file and am getting a hexadecimal color code. I need to create the corresponding System.Windows.Media.Color instance for the hexadecimal color code. Is there an inbuilt method in the framework to do this?

By hash code maybe they mean #00ff00?
Viky - don't refer to that as hash code. It's confusing. ;-) It's the hexadecimal representation of a color.
#FF0000 is an HTML (or hexadecimal) color code, not a hash code. Please learn the difference.
The symbol # is called hash in many countries, hence the confusion.
@axeman ??? You may have misunderstood what GetHashCode() in C# does. GetHashCode() is a method on every object in .NET. It does not return a hexadecimal value from the Color class.

T
Thorarin

I'm assuming that's an ARGB code... Are you referring to System.Drawing.Color or System.Windows.Media.Color? The latter is used in WPF for example. I haven't seen anyone mention it yet, so just in case you were looking for it:

using System.Windows.Media;

Color color = (Color)ColorConverter.ConvertFromString("#FFDFD991");

@Thorarin any help on how to get alpha value as I need to convert this value to be compatible with css rgba for web design.
@Yoda The first two digits (FF) are the alpha value. It's probably easier to use the Color.FromArgb method in this case though. If you use floating point alpha, you'd have to multiply by 255.
in case you have the RGB values -> Color.FromArgb(255,192,0)
string hex = "#FFFFFF"; Color _color = System.Drawing.ColorTranslator.FromHtml(hex);
why not use color.FromArgb() instead?
T
T.Todua

Assuming you mean the HTML type RGB codes (called Hex codes, such as #FFCC66), use the ColorTranslator class:

System.Drawing.Color col = System.Drawing.ColorTranslator.FromHtml("#FFCC66");

If, however you are using an ARGB hex code, you can use the ColorConverter class from the System.Windows.Media namespace:

Color col = ColorConverter.ConvertFromString("#FFDFD991") as Color;
//or      = (Color) ColorConverter.ConvertFromString("#FFCC66") ;

H
Hans Kesting

If you don't want to use the ColorTranslator, you can do it in easily:

string colorcode = "#FFFFFF00";
int argb = Int32.Parse(colorcode.Replace("#", ""), NumberStyles.HexNumber);
Color clr = Color.FromArgb(argb);

The colorcode is just the hexadecimal representation of the ARGB value.

EDIT

If you need to use 4 values instead of a single integer, you can use this (combining several comments):

string colorcode = "#FFFFFF00";    
colorcode = colorcode.TrimStart('#');

Color col; // from System.Drawing or System.Windows.Media
if (colorcode.Length == 6)
    col = Color.FromArgb(255, // hardcoded opaque
                int.Parse(colorcode.Substring(0,2), NumberStyles.HexNumber),
                int.Parse(colorcode.Substring(2,2), NumberStyles.HexNumber),
                int.Parse(colorcode.Substring(4,2), NumberStyles.HexNumber));
else // assuming length of 8
    col = Color.FromArgb(
                int.Parse(colorcode.Substring(0, 2), NumberStyles.HexNumber),
                int.Parse(colorcode.Substring(2, 2), NumberStyles.HexNumber),
                int.Parse(colorcode.Substring(4, 2), NumberStyles.HexNumber),
                int.Parse(colorcode.Substring(6, 2), NumberStyles.HexNumber));

Note 1: NumberStyles is in System.Globalization. Note 2: please provide your own error checking (colorcode should be a hexadecimal value of either 6 or 8 characters)


Color.FromArgb requires a, r, g, and b parameters, not an integer.
This is also useful if you are using the Compact Framework in which ColorTranslator is not available
@user1763532 - After colorcode = colorcode.Replace("#", "") simply use int a = byte.parse(colorcode.Substring(0,2), NumberStyles.HexNumber); and so on for r, g, and b. Don't forget to replace the first parameter of Substring - the index - with 2 for r, 4 for g and 6 for b.
@HansKesting, FromArgb takes 1 parameter in System.Drawing.Color and 4 paramteres in System.Windows.Media.Color
Note this works for a 4 byte (eg. #FFFFFFFF) HTML colour (inc alpha). If you try with a 3 byte (#FFFFFF) alpha will be 0 and your colour transparent. You can easilly insert alpha if the color code is less than 8/9 chars. Great for Compact Framework.
J
Jink

There is also this neat little extension method:

static class ExtensionMethods
{
    public static Color ToColor(this uint argb)
    {
        return Color.FromArgb((byte)((argb & -16777216)>> 0x18),      
                              (byte)((argb & 0xff0000)>> 0x10),   
                              (byte)((argb & 0xff00) >> 8),
                              (byte)(argb & 0xff));
    }
}

In use:

Color color = 0xFFDFD991.ToColor();

Maybe a stupid question, and a little late, but why do you use -16777216 for the alpha value?
Small variation consistently using hex: return Color.FromArgb((byte)((argb & 0xff000000) >> 0x18), (byte)((argb & 0xff0000) >> 0x10), (byte)((argb & 0xff00) >> 0x08), (byte)(argb & 0xff));
This code is faulty. I couldn't figure out why nothing was showing up and it turned out to be because this code doesn't convert hex to Color properly. I used the code from @too and that fixed it.
You can just do & 0xFF on the final downshifted value each time, instead of needing all those different values to & it with.
Doesn't Color.FromArgb have an overload that simply accepts an Int32 though? I mean, System.Drawing.Color sure does.
P
Peter Mortensen

The three variants below give exactly the same color. The last one has the benefit of being highlighted in the Visual Studio 2010 IDE (maybe it's ReSharper that's doing it) with proper color.

var cc1 = System.Drawing.ColorTranslator.FromHtml("#479DEE");

var cc2 = System.Drawing.Color.FromArgb(0x479DEE);

var cc3 = System.Drawing.Color.FromArgb(0x47, 0x9D, 0xEE);

None of these returns System.Windows.Media.Color.
C
ConfusedDeer

I needed to convert a HEX color code to a System.Drawing.Color, specifically a shade of Alice Blue as a background on a WPF form and found it took longer than expected to find the answer:

using System.Windows.Media;

--

System.Drawing.Color myColor = System.Drawing.ColorTranslator.FromHtml("#EFF3F7");
this.Background = new SolidColorBrush(System.Windows.Media.Color.FromArgb(myColor.A, myColor.R, myColor.G, myColor.B));

B
Baddack
    private Color FromHex(string hex)
    {
        if (hex.StartsWith("#"))
            hex = hex.Substring(1);

        if (hex.Length != 6) throw new Exception("Color not valid");

        return Color.FromArgb(
            int.Parse(hex.Substring(0, 2), System.Globalization.NumberStyles.HexNumber),
            int.Parse(hex.Substring(2, 2), System.Globalization.NumberStyles.HexNumber),
            int.Parse(hex.Substring(4, 2), System.Globalization.NumberStyles.HexNumber));
    }

In UWP Color.FromArgb() requires 4 byte arguments. So it will look like: return Color.FromArgb(255, byte.Parse(hex.Substring(0, 2), System.Globalization.NumberStyles.HexNumber), byte.Parse(hex.Substring(2, 2), System.Globalization.NumberStyles.HexNumber), byte.Parse(hex.Substring(4, 2), System.Globalization.NumberStyles.HexNumber));
P
Peter Mortensen

You could use the following code:

Color color = System.Drawing.ColorTranslator.FromHtml("#FFDFD991");

P
Peter Mortensen

If you want to do it with a Windows Store App, following by @Hans Kesting and @Jink answer:

    string colorcode = "#FFEEDDCC";
    int argb = Int32.Parse(colorcode.Replace("#", ""), NumberStyles.HexNumber);
    tData.DefaultData = Color.FromArgb((byte)((argb & -16777216) >> 0x18),
                          (byte)((argb & 0xff0000) >> 0x10),
                          (byte)((argb & 0xff00) >> 8),
                          (byte)(argb & 0xff));

J
Justin

This post has become the goto for anyone trying to convert from a hex color code to a system color. Therefore, I thought I'd add a comprehensive solution that deals with both 6 digit (RGB) and 8 digit (ARGB) hex values.

By default, according to Microsoft, when converting from an RGB to ARGB value

The alpha value is implicitly 255 (fully opaque).

This means by adding FF to a 6 digit (RGB) hex color code it becomes an 8 digit ARGB hex color code. Therefore, a simple method can be created that handles both ARGB and RGB hex's and converts them to the appropriate Color struct.

    public static System.Drawing.Color GetColorFromHexValue(string hex)
    {
        string cleanHex = hex.Replace("0x", "").TrimStart('#');

        if (cleanHex.Length == 6)
        {
            //Affix fully opaque alpha hex value of FF (225)
            cleanHex = "FF" + cleanHex;
        }

        int argb;

        if (Int32.TryParse(cleanHex, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out argb))
        {
            return System.Drawing.Color.FromArgb(argb);
        }

        //If method hasn't returned a color yet, then there's a problem
        throw new ArgumentException("Invalid Hex value. Hex must be either an ARGB (8 digits) or RGB (6 digits)");

    }

This was inspired by Hans Kesting's answer.


P
Peter Mortensen

You can see Silverlight/WPF sets ellipse with hexadecimal colour for using a hex value:

your_contorl.Color = DirectCast(ColorConverter.ConvertFromString("#D8E0A627"), Color)

P
Peter Mortensen

Use

System.Drawing.Color.FromArgb(myHashCode);

Glances over the conversion from hex string to int?
Originally the question was asked as "How to get a color from a hash code" which created a lot of confusion in here. ;-)
K
Khalil Al-rahman Yossefi

in asp.net:

color_black = (Color)new ColorConverter().ConvertFromString("#FF76B3");

ColorConverter is availabe in System.Drawing and System.Windows.Media. Which one do you mean (both are unrelated to ASP.NET)?
ColorConverter in System.Drawing can be used in ASP.NET
T
TERIHAX

You can use the ColorConverter.ConvertFromString(string) method which converts your string (hexadecimal) to the color.

Example: (This works with ARGB, like "#FF1E1E1E".

Control.Background = new SolidColorBrush((Color)ColorConverter.ConvertFromString("#1E1E1E"));

M
Max Truxa

WPF:

using System.Windows.Media;

//hex to color
Color color = (Color)ColorConverter.ConvertFromString("#7AFF7A7A");

//color to hex
string hexcolor = color.ToString();

Actually, there is no hex but Color [Indigo]
C
Cevdet

I used ColorDialog in my project. ColorDialog sometimess return "Red","Fhushia" and sometimes return "fff000". I solved this problem like this maybe help someone.

        SolidBrush guideLineColor;
        if (inputColor.Any(c => char.IsDigit(c)))
        {
            string colorcode = inputColor;
            int argbInputColor = Int32.Parse(colorcode.Replace("#", ""), NumberStyles.HexNumber);
             guideLineColor = new SolidBrush(Color.FromArgb(argbInputColor));

        }
        else
        {
            Color col = Color.FromName(inputColor);
             guideLineColor = new SolidBrush(col);
        }

InputColor is the return value from ColorDialog.

Thanks everyone for answer this question.It's big help to me.


M
MrPaulch

There are many answers here already.

In short I support those that propose to use System.Drawing.ColorTranslator.

I get that some people want to avoid System.Windows.Media so there is the other solution, and since you want to have a System.Drawing.Color you should have a reference to System.Drawing already in your project.

So in short: Use the Framework if you can.

A more complete native solution

So, if for some reason you want to avoid System.Drawing.ColorTranslator and create your own implementation, you should at least make it respect the specifications

So this is a solution that does #RGB and #RGBA shorthand - and extended color definition

    public static Color ParseHtmlColor(string htmlColor) => Color.FromArgb(HtmlColorToArgb(htmlColor));

    public static int HtmlColorToArgb(string htmlColor, bool requireHexSpecified = false, int defaultAlpha = 0xFF)
    {

        if (string.IsNullOrEmpty(htmlColor))
        {
            throw new ArgumentNullException(nameof(htmlColor));
        }

        if (!htmlColor.StartsWith("#") && requireHexSpecified)
        {
            throw new ArgumentException($"Provided parameter '{htmlColor}' is not valid");
        }

        htmlColor = htmlColor.TrimStart('#');
        

        // int[] symbols 
        var symbolCount = htmlColor.Length;
        var value = int.Parse(htmlColor, System.Globalization.NumberStyles.HexNumber);
        switch (symbolCount)
        {
            case 3: // RGB short hand
            {
                return defaultAlpha << 24
                    | (value & 0xF)
                    | (value & 0xF) << 4
                    | (value & 0xF0) << 4
                    | (value & 0xF0) << 8
                    | (value & 0xF00) << 8
                    | (value & 0xF00) << 12
                    ;
            }
            case 4: // RGBA short hand
            {
                // Inline alpha swap
                return   (value & 0xF) << 24
                       | (value & 0xF) << 28
                       | (value & 0xF0) >> 4
                       | (value & 0xF0) 
                       | (value & 0xF00) 
                       | (value & 0xF00) << 4
                       | (value & 0xF000) << 4
                       | (value & 0xF000) << 8
                       ;
            }
            case 6: // RGB complete definition
            {
                return defaultAlpha << 24 | value;   
            }
            case 8: // RGBA complete definition
            {
                // Alpha swap
                return (value & 0xFF) << 24 | (value >> 8);
            }
            default:
                throw new FormatException("Invalid HTML Color");
        }
    }

If you for some reason don't want to use System.Globalization I'm sure you'll find a code snipped for parsing hex symbols.

Tests

    public static void TestColors()
    {
        foreach (var testCase in TestCases) TestColor(testCase);
    }

    static string[] TestCases = new string[] { 
        "111",
        "FFF", 
        "17A",
        "F52",
        "444F",
        "2348",
        "4320",
        "121212",
        "808080",
        "FFFFFF",
        "A0E0C0",
        "0A070B",
        "FFFFFFFF",
        "808080FF",
        "40807710"
    };

    public static void TestColor(string htmlColor)
    {
        Console.Write($" {htmlColor} -> ");
        var color = ParseHtmlColor(htmlColor);
        Console.WriteLine("0x" + color.ToArgb().ToString("X"));
    }

P.S.: Feel free to remove the paramters, they only intend to show how you could tweak the function to handle format errors and defaults.

P.P.S.: The error messages are not very descriptive at the moment


S
Saamer

For any Xamarin developers out there, you will need to

Specify the color type in order to prevent Cast exception from assuming you are talking about Xamarin.Forms.Color instead Create an object of type ColorConverter

var conv = new System.Drawing.ColorConverter();
var color = (System.Drawing.Color)conv.ConvertFromString("#FF1D65AE");

G
Gerhard Schreurs

XNA / Monogame (Microsoft.Xna.Framework.Color).

Works for 6 or 8 (with alpha) character hexadecimal strings

Probably better alternatives (bit masking/shifting) out there.

    using Microsoft.Xna.Framework;
    using System.Globalization;
    
    public static class ColorBuilder
    {
        public static Color FromHex(string color)
        {
            var hex = color.Replace("#", string.Empty);
            var h = NumberStyles.HexNumber;

            var r = int.Parse(hex.Substring(0, 2), h);
            var g = int.Parse(hex.Substring(2, 2), h);
            var b = int.Parse(hex.Substring(4, 2), h);
            var a = 255;

            if (hex.Length == 8)
            {
                a = int.Parse(hex.Substring(6, 2), h);
            }
 
            return new Color(r, g, b, a);
        }
    }
    
    //create a blue color
    var color = ColorBuilder.FromHex("#2733C5"); //or ColorBuilder.FromHex("2733C5");
    
    //create a blue color with 50% alpha
    var colorTrans = ColorBuilder.FromHex("#2733C580");


P
Peter Mortensen

If you mean HashCode as in .GetHashCode(), I'm afraid you can't go back. Hash functions are not bi-directional, you can go 'forward' only, not back.

Follow Oded's suggestion if you need to get the color based on the hexadecimal value of the color.


@Wim Thanks for helping the OP clarify the question. I would say this answer is no longer needed, and recommend deleting it.