You can use a class 'ChatMessage' that contains a property 'MessageType'. It can check what type it is and draw itself in the right color. Something like this (unoptimized):

public class ChatMessage
{
    public Dictionary<string, Color> TypeColors
    {
        get;
        protected set;
    }

    private string MessageType;
    private string Text;
    private string UserName;
    private SpriteFont Font;
    
    public ChatMessage(string userName, string text, string type, SpriteFont font)// Gets all the data necessary
    {
        MessageType = type;
        Text = text;
        UserName = userName;
        Font = font;

        InitTypeColors();
    }

    protected void InitTypeColors()// Set these to what ever you want and add more
    {
        TypeColors = new Dictionary<string, Color>();
        TypeColors["normal"] = Color.Yellow;
        TypeColors["message"] = Color.White;
        TypeColors["system"] = Color.Red;
    }

    public void Draw (SpriteBatch batch, Vector2 position)
    {
        batch.DrawString(Font, UserName, position, TypeColors[MessageType]);// Draws the user name in one color
        batch.DrawString(Font, Text, new Vector2(position.X + Font.MeasureString(UserName).X + 15, position.Y), TypeColors["message"]);// then the message, 15 pixels to the right, in the color associated with that type
    }
}

Then in your game use a List for your chatList. In your Game Draw method replace this:

spriteBatch.DrawString(font, chatList[i], new Vector2(40, arr1[i]), Color.Yellow);

with this :

chatList[i].Draw(spriteBatch, new Vector2(40, arr1[i]));

That should work, but you may want to optimize the code a bit.

You can use a class 'ChatMessage' that contains a property 'MessageType'. It can check what type it is and draw itself in the right color. Something like this (unoptimized):

public class ChatMessage
{
    public Dictionary<string, Color> TypeColors
    {
        get;
        protected set;
    }

    private string MessageType;
    private string Text;
    private string UserName;
    private SpriteFont Font;
    
    public ChatMessage(string userName, string text, string type, SpriteFont font)// Gets all the data necessary
    {
        MessageType = type;
        Text = text;
        UserName = userName;
        Font = font;

        InitTypeColors();
    }

    protected void InitTypeColors()// Set these to what ever you want and add more
    {
        TypeColors = new Dictionary<string, Color>();
        TypeColors["normal"] = Color.Yellow;
        TypeColors["message"] = Color.White;
        TypeColors["system"] = Color.Red;
    }

    public void Draw (SpriteBatch batch, Vector2 position)
    {
        batch.DrawString(Font, UserName, position, TypeColors[MessageType]);// Draws the user name in one color
        batch.DrawString(Font, Text, new Vector2(position.X + Font.MeasureString(UserName).X + 15, position.Y), TypeColors["message"]);// then the message, 15 pixels to the right, in the color associated with that type
    }
}

Then in your game use a List<ChatMessage> for your chatList. In your Game Draw method replace this:

spriteBatch.DrawString(font, chatList[i], new Vector2(40, arr1[i]), Color.Yellow);

with this :

chatList[i].Draw(spriteBatch, new Vector2(40, arr1[i]));

That should work, but you may want to optimize the code a bit.

You can use a class 'ChatMessage' that contains a property 'MessageType'. It can check what type it is and draw itself in the right color. Something like this (unoptimized):

public class ChatMessage
{
    public Dictionary<string, Color> TypeColors
    {
        get;
        protected set;
    }

    private string MessageType;
    private string Text;
    private string UserName;
    private SpriteFont Font;
    
    public ChatMessage(string userName, string text, string type, SpriteFont font)// Gets all the data necessary
    {
        MessageType = type;
        Text = text;
        UserName = userName;
        Font = font;

        InitTypeColors();
    }

    protected void InitTypeColors()// Set these to what ever you want and add more
    {
        TypeColors = new Dictionary<string, Color>();
        TypeColors["normal"] = Color.Yellow;
        TypeColors["message"] = Color.White;
        TypeColors["system"] = Color.Red;
    }

    public void Draw (SpriteBatch batch, Vector2 position)
    {
        batch.DrawString(Font, UserName, position, TypeColors[MessageType]);// Draws the user name in one color
        batch.DrawString(Font, Text, new Vector2(position.X + Font.MeasureString(UserName).X + 15, position.Y), TypeColors["message"]);// then the message, 15 pixels to the right, in the color associated with that type
    }
}

Then in your game use a List for your chatList. In your Game Draw method replace this:

spriteBatch.DrawString(font, chatList[i], new Vector2(40, arr1[i]), Color.Yellow);

with this :

chatList[i].Draw(spriteBatch, new Vector2(40, arr1[i]));

that should work, but you may want to optimize the code a bit.

You can use a class 'ChatMessage' that contains a property 'MessageType'. It can check what type it is and draw itself in the right color. Something like this (unoptimized):

public class ChatMessage
{
    public Dictionary<string, Color> TypeColors
    {
        get;
        protected set;
    }

    private string MessageType;
    private string Text;
    private string UserName;
    private SpriteFont Font;
    
    public ChatMessage(string userName, string text, string type, SpriteFont font)// Gets all the data necessary
    {
        MessageType = type;
        Text = text;
        UserName = userName;
        Font = font;

        InitTypeColors();
    }

    protected void InitTypeColors()// Set these to what ever you want and add more
    {
        TypeColors = new Dictionary<string, Color>();
        TypeColors["normal"] = Color.Yellow;
        TypeColors["message"] = Color.White;
        TypeColors["system"] = Color.Red;
    }

    public void Draw (SpriteBatch batch, Vector2 position)
    {
        batch.DrawString(Font, UserName, position, TypeColors[MessageType]);// Draws the user name in one color
        batch.DrawString(Font, Text, new Vector2(position.X + Font.MeasureString(UserName).X + 15, position.Y), TypeColors["message"]);// then the message, 15 pixels to the right, in the color associated with that type
    }
}

Then in your game use a List for your chatList. In your Game Draw method replace this:

spriteBatch.DrawString(font, chatList[i], new Vector2(40, arr1[i]), Color.Yellow);

with this :

chatList[i].Draw(spriteBatch, new Vector2(40, arr1[i]));

That should work, but you may want to optimize the code a bit.