Question

Why is:

(CheckBox)lstControls.Where(x => x.ID == 'some_id').SingleOrDefault(); 

not as efficient as:

(CheckBox)lstControls.SingleOrDefault(x => x.ID == 'some_id'); 

And for a not-so-well-formed XML document and you only know the name of the element you are looking for is this the best statement you can use to find the element:

var xmlElem = (from n in xDocument.Descendants() where (string)n.Attribute('name') == 'some_node_name' select n).SingleOrDefault(); 

Thanks….

Answer 1

If I’m not mistaken, in terms of big O efficiency, it’s the same. It’s just an extra method call.

Regarding the second question,

var xmlElem = (from n in xDocument.Descendants() where (string)n.Attribute('name') == 'some_node_name' select n).SingleOrDefault(); 

can be expressed more simply as

var xmlElem = xDocument.Descendants().SingleOrDefault(n => (string)n.Attribute('name') == 'some_node_name');