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Why does one often see “null != variable” instead of “variable != null” in C#?
...r (and is indeed legal code):
// Probably wrong
if (x = 5)
when you actually probably meant
if (x == 5)
You can work around this in C by doing:
if (5 == x)
A typo here will result in invalid code.
Now, in C# this is all piffle. Unless you're comparing two Boolean values (which is rare, IME...
Combined area of overlapping circles
...
Find all circle intersections on the outer perimeter (e.g. B,D,F,H on the following diagram). Connect them together with the centres of the corresponding circles to form a polygon. The area of the union of the circles is the area ...
GetHashCode Guidelines in C#
...ot GetHashCode right at every implementation. Second, value types are generally immutable with every value being a new instance rather than a modification of an existing instance.
– Jeff Yates
Jan 20 '09 at 18:46
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What is the difference between a pseudo-class and a pseudo-element in CSS?
...nsists of a "colon" (:) followed by the name of the pseudo-class and optionally by a value between parentheses.
Pseudo-classes are allowed in all sequences of simple selectors contained in a selector. Pseudo-classes are allowed anywhere in sequences of simple selectors, after the leading type s...
How to force an entire layout View refresh?
...Invalidate the whole view. If the view is visible, onDraw(Canvas) will be called at some point in the future. This must be called from a UI thread. To call from a non-UI thread, call postInvalidate().
ViewGroup vg = findViewById (R.id.mainLayout);
vg.invalidate();
Now, when the Activity resume...
SQL - The conversion of a varchar data type to a datetime data type resulted in an out-of-range valu
...s with the time zone setting. Specify in other formats like mm/dd/yyyy (usually works).
Specifying the date as 30/12/2013 resulted in the error for me. However, specifying it as mm/dd/yyyy format worked.
If you need to convert your input the you can try looking into the CONVERT method.
Syntax i...
Cannot set some HTTP headers when using System.Net.WebRequest
...ht to the last section of the answer.
If you want to know better, read it all, and i hope you'll enjoy...
I countered this problem too today, and what i discovered today is that:
the above answers are true, as:
1.1 it's telling you that the header you are trying to add already exist and you s...
What is the difference between a URI, a URL and a URN?
...tion"). The term "Uniform Resource Name"
(URN) has been used historically to refer to both URIs under the
"urn" scheme [RFC2141], which are required to remain globally unique
and persistent even when the resource ceases to exist or becomes
unavailable, and to any other URI with ...
The Following Module was built either with optimizations enabled or without debug information
...ode on the non-web project in question and it's in Active(Debug). Deleted all items in my .NET 2.0 temp folder in Windows. Not sure what else to do here.
...
Counting the number of elements with the values of x in a vector
...
Don't forget about potential floating point issues, especially with table, which coerces numbers to strings.
– hadley
Dec 17 '09 at 18:10
4
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