Question

How do I make the below exception return BOLD and text font RED? The wordings of “return “WMI Error“;”

This is used later in the code for returning WMI parameters in a textbox…as shown below:

 private static string GetMOValue(ManagementObject mo, string name)
        {
            try
            {
                object result = mo[name];
                return result == null ? "" : result.ToString();
            }
            catch (Exception)
            {
                return "***WMI Error***";
            }
        }

        private void cmbHdd_SelectedIndexChanged(object sender, EventArgs e)
        {
            //try
            //{
                ManagementObjectSearcher mosDisks = new ManagementObjectSearcher("SELECT * FROM Win32_DiskDrive WHERE Model = '" + cmbHdd.SelectedItem + "'");
                foreach (ManagementObject moDisk in mosDisks.Get())
                {
                    //try
                    //{
                    txtSystemName.Text = GetMOValue(moDisk, "systemname");
                    txtType.Text = GetMOValue(moDisk, "MediaType");
                    txtModel.Text = GetMOValue(moDisk, "Model");
                    txtFirmware.Text = GetMOValue(moDisk, "FirmwareRevision");
.....

Answer 1

TextBox is not a web browser. It supports showing text with a single font – no decorations, colors, etc. You can change a font for the textbox in runtime.

You could handle the TextChanged event of the textbox to achieve this, but this is not an example of nice code:

private void textBox1_TextChanged(object sender, EventArgs e)
{
  Font defaultFont = SystemFonts.DefaultFont;

  if(textBox1.Text.StartsWith("**") && textBox1.Text.EndsWith("**"))
  {
    textBox1.Font = new Font(defaultFont.FontFamily, defaultFont.Size, FontStyle.Bold);
    textBox1.ForeColor = Color.Red;
    // note: can't change text here as it will recursively trigger this handler
  }
  else
  {
    textBox1.Font = defaultFont;
    textBox1.ForeColor = SystemColors.ControlText;
  }
}

A better approach would be to have a simple method which will set the text and textbox attributes.

the soapbox: Please note that I consider this form of checking the text for ** characters to see if it is an error, extremely ugly and unreliable. What you should do is have something like

Font defaultFont = SystemFonts.DefaultFont;
try
{ 
   textBox1.Text = GetMOValue(...);
   textBox1.Font = defaultFont;
   textBox1.ForeColor = SystemColors.ControlText;
}
catch(Exception ex)
{ 
   textBox1.Text = "ERROR";
   textBox1.Font = new Font(defaultFont.FontFamily, defaultFont.Size, FontStyle.Bold);
   textBox1.ForeColor = Color.Red;
}
// the Font and ForeColor properties are repeatedly set in case that previous
// try had the different result (e.g. previous => error, current => OK, so 
// we need to reset the attributes of textbox

You can use RichTextBox, WebBrowser or some custom drawn control to support fancier formatting.