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What is the C# equivalent to Java's isInstance()?
...
Depends, use is if you don't want to use the result of the cast and use as if you do. You hardly ever want to write:
if(foo is Bar) {
return (Bar)foo;
}
Instead of:
var bar = foo as Bar;
if(bar != null) {
return bar;
}
...
Why is the default value of the string type null instead of an empty string?
..., and (2) an unfortunate extra layer of boxing indirection any time it was cast to Object. Given that the heap representation of string is unique, having special treatment to avoid extra boxing wouldn't have been much of a stretch (actually, being able to specify non-default boxing behaviors would ...
SQL select join: is it possible to prefix all columns as 'prefix.*'?
...result set for a list of columns in a scripting language such as Python or PHP.
SELECT '' as table1_dummy, table1.*, '' as table2_dummy, table2.*, '' as table3_dummy, table3.* FROM table1
JOIN table2 ON table2.table1id = table1.id
JOIN table3 ON table3.table1id = table1.id
I realize this doesn't ...
Why is Multiple Inheritance not allowed in Java or C#?
...s a lot of complexity into the
implementation. This complexity
impacts casting, layout, dispatch,
field access, serialization, identity
comparisons, verifiability,
reflection, generics, and probably
lots of other places.
You can read the full article here.
For Java, you can read th...
How to avoid warning when introducing NAs by coercion
...Not the answer you're looking for? Browse other questions tagged r parsing casting na or ask your own question.
Facebook Graph API v2.0+ - /me/friends returns empty, or only friends who also use my application
... && l.GetAttributeValue("data-hovercard").Contains("user.php")
&& l.Text != null
).LastOrDefault();
if (lastLink == null || previousLastLink == lastLink)
{
break;
}
var ieElement = lastLink.Native...
How do I get a plist as a Dictionary in Swift?
... type Array<AnyObject>, but we know what type it really is so we can cast it to the correct type:
let dictArray = plist as! [[String:String]]
// [[String:String]] is equivalent to Array< Dictionary<String, String> >
And now we can access the various properties of our Array of St...
Reshaping data.frame from wide to long format
...
reshape() takes a while to get used to, just as melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
...
Java EE web development, where do I start and what skills do I need? [closed]
..., css, etc) just like a web server does. It is comparable to Apache with a php module.
– Nemi
Dec 24 '09 at 16:16
add a comment
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Reliable method to get machine's MAC address in C#
...d=true");
IEnumerable<ManagementObject> objects = searcher.Get().Cast<ManagementObject>();
string mac = (from o in objects orderby o["IPConnectionMetric"] select o["MACAddress"].ToString()).FirstOrDefault();
return mac;
}
Or in Silverlight (needs elevated trust):
public st...