Question: I am developing an outlook add-in, i have a form with a button which has a "Close.png" icon the Imagesource of the button is 

```
<Button.Background>
            <ImageBrush ImageSource="pack://siteoforigin:,,,/Resources/Close.png"/>
            </Button.Background>

```

, when i deploy the solution using clickonce and after install it successfully and when i tried to run it from outlook y got the following exception message: "\Addin.Outlook\Addin.Outlook\publish\Resources\Close.png", having Content as build action and copy always as copy to output directory.
I need some help, cheers.

Answer: 
Just combine [`in_array()`](http://php.net/manual/en/function.in-array.php) with [`range()`](http://php.net/manual/en/function.range.php), like this:

```
if(!in_array($x, range(400, 550)))
   echo "in ";
echo "valid";

```

Or just do a simple if statement, e.g.

```
if($x >= 400 && $x <= 550)

```
Should work :

```
^((4\d\d)|(5([0-4]\d|50)))$

```