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Using the default constructor T variable = Activator.CreateInstance(typeof(T)); Using parameterized constructor T variable = Activator.CreateInstance(typeof(T), arg1, arg2);

Occasionally you'd want to catch an exception and throw it from a different thread or method while preserving the original exception stack. This can be done with ExceptionDispatchInfo: using System.Runtime.ExceptionServices; void Main() { ExceptionDispatchInfo capturedException = null; ...

First, import the libraries that work with files: from os import listdir from os.path import isfile, join, exists A helper function to read only files from a directory: def get_files(path): for file in listdir(path): full_path = join(path, file) if isfile(full_path): ...

Syntax: add_months(p_date, integer) return date; Add_months function adds amt months to p_date date. SELECT add_months(date'2015-01-12', 2) m FROM dual; M2015-03-12 You can also substract months using a negative amt SELECT add_months(date'2015-01-12', -2) m FROM dual; M2014-11-12 When the...

public static class ThreadLocalExample { private static final ThreadLocal<SimpleDateFormat> format = ThreadLocal.withInitial(() -> new SimpleDateFormat("yyyyMMdd_HHmm")); public String formatDate(Date date) { return format.get().format(date); ...

PHP has great official documentation already at http://php.net/manual/. The PHP Manual documents pretty much all language features, the core libraries and most available extensions. There are plenty of examples to learn from. The PHP Manual is available in multiple languages and formats. Best of al...

// *** Case Insensitive comparison with exact title match *** NSPredicate *filterByNameCIS = [NSPredicate predicateWithFormat:@"self.title LIKE[cd] %@",@"Tom and Jerry"]; NSLog(@"Filter By Name(CIS) : %@",[array filteredArrayUsingPredicate:filterByNameCIS]);

// *** Case Insensitive comparison with matching subset *** NSPredicate *filterByName = [NSPredicate predicateWithFormat:@"self.title CONTAINS[cd] %@",@"Tom"]; NSLog(@"Filter By Containing Name : %@",[array filteredArrayUsingPredicate:filterByName]);

An enumeration is a user-defined data type consists of integral constants and each integral constant is given a name. Keyword enum is used to define enumerated data type. If you use enum instead of int or string/ char*, you increase compile-time checking and avoid errors from passing in invalid con...

There are times in which it is desirable to consolidate factor levels into fewer groups, perhaps because of sparse data in one of the categories. It may also occur when you have varying spellings or capitalization of the category names. Consider as an example the factor set.seed(1) colorful <...

It is usually not a good idea to mix signed and unsigned integers in arithmetic operations. For example, what will be output of following example? #include <stdio.h> int main(void) { unsigned int a = 1000; signed int b = -1; if (a > b) puts("a is more than b&quot...

There are multiple ways to set a key's object in an NSDictionary, corresponding to the ways you get a value. For instance, to add a lamborghini to a list of cars Standard [cars setObject:lamborghini forKey:@"Lamborghini"]; Just like any other object, call the method of NSDictionary th...

There are multiple ways to get an object from an NSDictionary with a key. For instance, to get a lamborghini from a list of cars Standard Car * lamborghini = [cars objectForKey:@"Lamborghini"]; Just like any other object, call the method of NSDictionary that gives you an object for a ...

The simplest way to concatenate list1 and list2: merged = list1 + list2 zip returns a list of tuples, where the i-th tuple contains the i-th element from each of the argument sequences or iterables: alist = ['a1', 'a2', 'a3'] blist = ['b1', 'b2', 'b3'] for a, b in zip(alist, blist):...

from container to host docker cp CONTAINER_NAME:PATH_IN_CONTAINER PATH_IN_HOST from host to container docker cp PATH_IN_HOST CONTAINER_NAME:PATH_IN_CONTAINER If I use jess/transmission from https://hub.docker.com/r/jess/transmission/builds/bsn7eqxrkzrhxazcuytbmzp/ , the files in the contai...

Represents a thread-safe collection of key/value pairs that can be accessed by multiple threads concurrently. Creating an instance Creating an instance works pretty much the same way as with Dictionary<TKey, TValue>, e.g.: var dict = new ConcurrentDictionary<int, string>(); Ad...

Defining a method in Ruby 2.x returns a symbol representing the name: class Example puts def hello end end #=> :hello This allows for interesting metaprogramming techniques. For instance, methods can be wrapped by other methods: class Class def logged(name) original_method...

You can use a For Each...Next loop to iterate through any IEnumerable type. This includes arrays, lists, and anything else that may be of type IEnumerable or returns an IEnumerable. An example of looping through a DataTable's Rows property would look like this: For Each row As DataRow In DataTable...

The following example shows how you can use Json.Net to serialize the data in an C# Object's instance, to JSON string. using System; using System.Collections.Generic; using Newtonsoft.Json; public class Employee { public string FirstName { get; set; } public string LastName { get; s...

The following example shows how you can deserialize a JSON string containing into an Object (i.e. into an instance of a class). using System; using System.Collections.Generic; using Newtonsoft.Json; public class Program { public class Employee { public s...