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What's the difference between an object initializer and a constructor?
...nstances of one or more other classes. For example see File.Create Method (String) (and its overloads) which creates a FileStream object.
– DavidRR
Jan 17 '18 at 18:13
add a c...
Returning binary file from controller in ASP.NET Web API
...t.Http;
// using System.Net.Http.Headers;
public HttpResponseMessage Post(string version, string environment,
string filetype)
{
var path = @"C:\Temp\test.exe";
HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
var stream = new FileStream(path, FileMode.Open, ...
Determine the data types of a data frame's columns
...integer" "logical" "factor"
Using str() gets you that information plus extra goodies (such as the levels of your factors and the first few values of each variable):
str(my.data)
'data.frame': 5 obs. of 4 variables:
$ y : num 1.03 1.599 -0.818 0.872 -2.682
$ x1: int 1 2 3 4 5
$ x2: logi T...
How to test code dependent on environment variables using JUnit?
...onmentVariablesTest {
@Test
public void setEnvironmentVariable() {
String value = withEnvironmentVariable("name", "value")
.execute(() -> System.getenv("name"));
assertEquals("value", value);
}
}
For Java 5 to 7 the library System Rules has a JUnit rule called EnvironmentVari...
Why not abstract fields?
...ised in its constructor (untested code):
abstract class Base {
final String errMsg;
Base(String msg) {
errMsg = msg;
}
abstract String doSomething();
}
class Sub extends Base {
Sub() {
super("Sub message");
}
String doSomething() {
return e...
How can a LEFT OUTER JOIN return more records than exist in the left table?
...ually want you can use aggregate functions (if for example you just want a string from the right part you could generate a column that is a comma delimited string of the right side results for that left row.
If you are only looking at 1 or 2 columns from the outer join you might consider using a sc...
How to check if an object is a list or tuple (but not string)?
...
In python 2 only (not python 3):
assert not isinstance(lst, basestring)
Is actually what you want, otherwise you'll miss out on a lot of things which act like lists, but aren't subclasses of list or tuple.
share...
Why Response.Redirect causes System.Threading.ThreadAbortException?
...ew Context)
{
User User = new User();
if (String.IsNullOrEmpty(model.EmailAddress))
ValidLogin = false; // no email address was entered
else
User = Db.FirstOrDefault(x => x.EmailAddress == model.EmailAddress);
...
Hash function that produces short hashes?
Is there a way of encryption that can take a string of any length and produce a sub-10-character hash? I want to produce reasonably unique ID's but based on message contents, rather than randomly.
...
Use of *args and **kwargs [duplicate]
...med arguments come first in the list. For example:
def table_things(titlestring, **kwargs)
You can also use both in the same function definition but *args must occur before **kwargs.
You can also use the * and ** syntax when calling a function. For example:
>>> def print_three_things...