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Is there a reason for C#'s reuse of the variable in a foreach?
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8.8.4 The foreach statement
(...)
A foreach statement of the form
foreach (V v in x) embedded-statement
is then expanded to:
{
E e = ((C)(x)).GetEnumerator();
try {
while (e.MoveNext()) {
V v = (V)(T)e.Current;
embedded-statement
}
}
fina...
How do I get java logging output to appear on a single line?
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As of Java 7, java.util.logging.SimpleFormatter supports getting its format from a system property, so adding something like this to the JVM command line will cause it to print on one line:
-Djava.util.logging.SimpleFormatter.format='%1$tY-%1$tm-%1$td %1$tH:%1$t...
How to round a number to n decimal places in Java
...ode explicitly to handle your issue with the half-even round, then use the format pattern for your required output.
Example:
DecimalFormat df = new DecimalFormat("#.####");
df.setRoundingMode(RoundingMode.CEILING);
for (Number n : Arrays.asList(12, 123.12345, 0.23, 0.1, 2341234.212431324)) {
D...
What is the !! (not not) operator in JavaScript?
I saw some code that seems to use an operator I don't recognize, in the form of two exclamation points, like so: !! . Can someone please tell me what this operator does?
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C#: Looping through lines of multiline string
...l etc :) Having said that, if you do want to do a manual loop, this is the form that I typically prefer over Fredrik's:
using (StringReader reader = new StringReader(input))
{
string line;
while ((line = reader.ReadLine()) != null)
{
// Do something with the line
}
}
This ...
List comprehension: Returning two (or more) items for each item
...cause it does not require recreating the list on every + (thus has O(N) performance rather than O(N^2) performance). I'll still use sum(..., []) when I want a quick one-liner or I'm in a hurry, or when the number of terms being combined is bounded (e.g. <= 10).
– ninjagecko
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How to improve performance of ngRepeat over a huge dataset (angular.js)?
...e 10 times and every press add 100 more items, how can this improve the performance?
– hariszaman
Sep 10 '15 at 11:47
5
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
...hen the database helper constructor is called with a name (2nd param), platform checks if the database exists or not and if the database exists, it gets the version information from the database file header and triggers the right call back
As already explained in the older answer, if the database w...
How to pass a single object[] to a params object[]
...sed to in other languages. params could have been made to only accept one form, and a spread like feature could be added that would benefit the entire language, not just this case. for example, we could force all param calls to be Foo(obj[0], obj[1]), and then have a separate spread operator allow...
Different ways of adding to Dictionary
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The performance is almost a 100% identical. You can check this out by opening the class in Reflector.net
This is the This indexer:
public TValue this[TKey key]
{
get
{
int index = this.FindEntry(key);
if (i...