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For Alerts since iOS 8, you would use a UIAlertController but for versions before, you would have used a UIAlertView, which is now deprecated. 8.0 var alert = UIAlertController.Create(title, message, UIAlertControllerStyle.Alert); alert.AddAction(UIAlertAction.Create(otherTitle, UIAlertActionStyl...

To pass data from the current view controller to the next new view controller (not a previous view controller) using segues, first create a segue with an identifier in the relevant storyboard. Override your current view controller's prepareForSegue method. Inside the method check for the segue you j...

We can make an AJAX request to Stack Exchange's API to retrieve a list of the top JavaScript questions for the month, then present them as a list of links. If the request fails or the returns an API error, our promise error handling displays the error instead. 6 View live results on HyperWeb. c...

A data.frame is a special kind of list: it is rectangular. Each element (column) of the list has same length, and where each row has a "row name". Each column has its own class, but the class of one column can be different from the class of another column (unlike a matrix, where all elemen...

In order to begin building with PayPal APIs, you have to create an application to obtain a client ID and secret. Go to https://developer.paypal.com/developer/applications/, sign in, and click on "Create App", as shown below: Next, enter an application name, select the sandbox testing a...

When testing you PayPal integration on sandbox, you'll need to have sandbox user accounts set up to use to go through the payment flow. Go to https://developer.paypal.com/developer/accounts/, log in using your PayPal account, and click on "Create Account", as below: Enter in the accoun...

cat file.txt will print the contents of a file. If the file contains non-ASCII characters, you can display those characters symbolically with cat -v. This can be quite useful for situations where control characters would otherwise be invisible. cat -v unicode.txt Very often, for interactive ...

Use the --number flag to print line numbers before each line. Alternatively, -n does the same thing. $ cat --number file 1 line 1 2 line 2 3 4 line 4 5 line 5 To skip empty lines when counting lines, use the --number-nonblank, or simply -b. $ cat -b file 1 line 1 2 line ...

man <command> This will show the manual page for the specified command. For example, man ping will show: PING(8) BSD System Manager's Manual PING(8) NAME ping -- send ICMP ECHO_REQUEST packets to network hosts SYNOPSIS ping [-AaCDdfno...

$url = "https://api.dropboxapi.com/2/sharing/share_folder" $req = [System.Net.HttpWebRequest]::Create($url) $req.headers["Authorization"] = "Bearer <ACCESS_TOKEN>" $req.Method = "POST" $req.ContentType = "application/json" $enc = [system...

$url = "https://api.dropboxapi.com/2/users/get_current_account" $req = [System.Net.HttpWebRequest]::Create($url) $req.headers["Authorization"] = "Bearer <ACCESS_TOKEN>" $req.Method = "POST" $res = $req.GetResponse() Write-Host "Response Sta...

Start by installing the PayPal Node module from NPM npm install paypal-rest-sdk In your application file, add in the configuration information for the SDK var paypal = require('paypal-rest-sdk'); var client_id = 'YOUR CLIENT ID'; var secret = 'YOUR SECRET'; paypal.configure({ 'mode'...

Consider the below list comprehension: >>> def f(x): ... import time ... time.sleep(.1) # Simulate expensive function ... return x**2 >>> [f(x) for x in range(1000) if f(x) > 10] [16, 25, 36, ...] This results in two calls to f(x) for 1,000 values of...

Defining a new protocol: @protocol NewProtocol - (void)protocolMethod:(id)argument; - (id)anotherMethod; @end

In this example, we're going to set up an Express server integration to display how to process a payment with PayPal, using the PayPal Node SDK. We will use a static JSON structure for the payment details for the sake of brevity. There are three general steps that we will follow when building out t...

The !important declaration is used to override the usual specificity in a style sheet by giving a higher priority to a rule. Its usage is: property : value !important; #mydiv { font-weight: bold !important; /* This property won't be overridden by the ...

Data Manipulation Language (DML for short) includes operations such as INSERT, UPDATE and DELETE: -- Create a table HelloWorld CREATE TABLE HelloWorld ( Id INT IDENTITY, Description VARCHAR(1000) ) -- DML Operation INSERT, inserting a row into the table INSERT INTO HelloWorld (D...

If you need to use the ^ character in a character class (Character classes ), either put it somewhere other than the beginning of the class: [12^3] Or escape the ^ using a backslash \: [\^123] If you want to match the caret character itself outside a character class, you need to escape it: ...

The simplest form of macro replacement is to define a manifest constant, as in #define ARRSIZE 100 int array[ARRSIZE]; This defines a function-like macro that multiplies a variable by 10 and stores the new value: #define TIMES10(A) ((A) *= 10) double b = 34; int c = 23; TIMES10(b); //...

Swift's built-in numeric types are: Word-sized (architecture-dependent) signed Int and unsigned UInt. Fixed-size signed integers Int8, Int16, Int32, Int64, and unsigned integers UInt8, UInt16, UInt32, UInt64. Floating-point types Float32/Float, Float64/Double, and Float80 (x86-only). Literal...