C# How to handle an Image exception in a Windows Phone 8.0 Silverlight App -

using httpclient htmlagility pack in windows phone 8.0 silverlight app.

i'd know how manage exception image isn't contained in particular node.

for example, missing text, use following:

var notitle = div.selectsinglenode(".//h3"); if (notitle == null || string.isnullorempty((notitle.innertext ?? "").trim()))     newgame.title = "unavailable"; else     newgame.title = div.selectsinglenode(".//h3").innertext.trim();  

but, how code missing img src? default code, without exception handling is:

newgame.cover = div.selectsinglenode(".//img[@class= 'box1']").attributes["src"].value; 

ideally, use own image file if 1 not contained within node (e.g. "/assets/images/unavailable.png")

thanks in advance.

31/01/2016 - added html code

this snippet of html i'm getting info from.

<div class="game-c">     <div class="boxshot">     <img class="cover" src="http://cover_source" />     </div>     <h3 class="h3 white-c">game title ...</h3>     <p>game description goes here...</p>     <p>...</p>     <div class="cta-signedout">...</div>     <div class="cta-signedin">         <a href="https://link.to.store">          <img src="gameimage.gif" /></a>     </div> </div> 

i need img src 'cta-signedin'.

htmlagilitypack has getattributevalue() method suitable requirement. 2nd parameter of method specify default value returned when attribute not found :

newgame.cover = div.selectsinglenode(".//img[@class= 'box1']")                    .getattributevalue("src", "/assets/images/unavailable.png"); 

the above snippet assumed <img> element exists, it's src attribute missing. otherwise, you'll need check whether or not selectsinglenode() returns null first.

here simple working demo example :

var html = @"<div><img/></div>"; htmldocument doc = new htmldocument(); doc.loadhtml(html);  var src = doc.documentnode              .selectsinglenode("//img")              .getattributevalue("src", "/assets/images/unavailable.png"); console.writeline(src); 

dotnetfiddle demo

output :

/assets/images/unavailable.png