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How to do constructor chaining in C#
...), d = new Foo("abc");
Note also:
you can chain to constructors on the base-type using base(...)
you can put extra code into each constructor
the default (if you don't specify anything) is base()
For "why?":
code reduction (always a good thing)
necessary to call a non-default base-constructo...
How do I lock the orientation to portrait mode in a iPhone Web Application?
...
You can specify CSS styles based on viewport orientation:
Target the browser with body[orient="landscape"] or body[orient="portrait"]
http://www.evotech.net/blog/2007/07/web-development-for-the-iphone/
However...
Apple's approach to this issue is to...
Is there a benefit to defining a class inside another class in Python?
...It is just a way of collecting some variables - the name of the class, the bases, a little dictionary of attributes, and a metaclass.
The name, the dictionary and the bases are all passed to the function that is the metaclass, and then it is assigned to the variable 'name' in the scope where the cl...
C++ equivalent of Java's toString?
...
You can also do it this way, allowing polymorphism:
class Base {
public:
virtual std::ostream& dump(std::ostream& o) const {
return o << "Base: " << b << "; ";
}
private:
int b;
};
class Derived : public Base {
public:
virtual std::ostream...
Convert a list of data frames into one data frame
... Nice solution. .id = "column_label" adds the unique row names based on the list element names.
– Sibo Jiang
Apr 29 '18 at 20:49
13
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Why java.lang.Object is not abstract? [duplicate]
Why is the Object class, which is base class of 'em all in Java, not abstract?
14 Answers
...
YouTube API to fetch all videos on a channel
...oChannelId=UC*****ntcQ&key=AI*****k
Here all api's are Get approach.
Based on channel id we con't get all videos directly, that's the important point here.
For integration https://developers.google.com/youtube/v3/quickstart/ios?ver=swift
...
Deleting all records in a database table
How do I delete all records in one of my database tables in a Ruby on Rails app?
7 Answers
...
Split comma-separated strings in a column into separate rows
... is the fastest1.
The benchmarked solutions include
Matthew Lundberg's base R approach but modified according to Rich Scriven's comment,
Jaap's two data.table methods and two dplyr / tidyr approaches,
Ananda's splitstackshapesolution,
and two additional variants of Jaap's data.table methods.
...
Filter rows which contain a certain string
...good things about Stringr
We should use rather stringr::str_detect() than base::grepl(). This is because there are the following reasons.
The functions provided by the stringr package start with the prefix str_, which makes the code easier to read.
The first argument of the functions of stringr p...