Tutorial by Examples: le

From documentation: The HttpContext.Items collection is the best location to store data that is only needed while processing a given request. Its contents are discarded after each request. It is best used as a means of communicating between components or middleware that operate at different poi...

Django 1.10 introduced a new middleware style where process_request and process_response are merged together. In this new style, a middleware is a callable that returns another callable. Well, actually the former is a middleware factory and the latter is the actual middleware. The middleware facto...

The latest version of the Oracle Java style guide mandates that the "then" and "else" statements in an if statement should always be enclosed in "braces" or "curly brackets". Similar rules apply to the bodies of various loop statements. if (a) { //...

Create blank Multi-Device (Firemonkey) application. Drop Rectangle on Form. In Object inspector window (F11) find RotationAngle click on drop down button, and select "Create New TFloatAnimation". Object inspector window is automatically switched to a newly added TFloatAnimation, you...

Google Perf Tools also provides a CPU profiler, with a slightly friendlier interface. To use it: Install Google Perf Tools Compile your code as usual Add the libprofiler profiler library to your library load path at runtime Use pprof to generate a flat execution profile, or a callgraph diagram...

The | can be used to have a single case statement match against multiple inputs to yield the same result: def f(str: String): String = str match { case "foo" | "bar" => "Matched!" case _ => "No match." } f("foo") // res0: String = M...

Given the following List of tuples: val pastries = List(("Chocolate Cupcake", 2.50), ("Vanilla Cupcake", 2.25), ("Plain Muffin", 3.25)) Pattern matching can be used to handle each element differently: pastries foreach { pa...

The std::nth_element algorithm takes three iterators: an iterator to the beginning, nth position, and end. Once the function returns, the nth element (by order) will be the nth smallest element. (The function has more elaborate overloads, e.g., some taking comparison functors; see the above link for...

Print the path to the active developer directory (selected Xcode) xcode-select -p Select a different version of Xcode, e.g. Beta sudo xcode-select -s /Applications/Xcode-beta.app Reset to the default version of Xcode sudo xcode-select -r This is equivalent to running sudo xcode-select -s /Appl...

When pasting text through a terminal emulator, the auto-indent feature may destroy the indentation of the pasted text. For example: function () { echo 'foo' echo 'bar' echo 'baz' } will be pasted as: function () { echo 'foo' echo 'bar' echo 'baz' ...

To delete a file (if you have required permissions) is as simple as: File.Delete(path); However many things may go wrong: You do not have required permissions (UnauthorizedAccessException is thrown). File may be in use by someone else (IOException is thrown). File cannot be deleted because ...

To change a text file is not easy because its content must be moved around. For small files easiest method is to read its content in memory and then write back modified text. In this example we read all lines from a file and drop all blank lines then we write back to original path: File.WriteAllLi...

Text is saved encoded (see also Strings topic) then sometimes you may need to change its encoding, this example assumes (for simplicity) that file is not too big and it can be entirely read in memory: public static void ConvertEncoding(string path, Encoding from, Encoding to) { File.WriteAllT...

This example updates last write time of a huge number of files (using System.IO.Directory.EnumerateFiles instead of System.IO.Directory.GetFiles()). Optionally you can specify a search pattern (default is "*.*" and eventually search through a directory tree (not only the specified director...

This snippet is an helper function to enumerate all files older than a specified age, it's useful - for example - when you have to delete old log files or old cached data. static IEnumerable<string> EnumerateAllFilesOlderThan( TimeSpan maximumAge, ...

echo off cls sqlcmd.exe -S "your server name" -U "sql user name" -P "sql password" -d "name of databse" -Q "here you may write your query/stored procedure" Batch files like these can be used to automate tasks, for example to make backups of ...

It is obvious to assume that the percentage value of margin to margin-left and margin-right would be relative to its parent element. .parent { width : 500px; height: 300px; } .child { width : 100px; height: 100px; margin-left: 10%; /* (parentWidth * 10/100) => 50px ...

This can be done in the following two ways - cts:search( fn:collection("first-collection"), cts:word-query("marklogic")) In this, the scope is changed from all the documents to documents in collection "first-collection" only. In the second approach, use ...

This query returns all the documents with element "company" and its value as "marklogic" cts:element-value-query(xs:QName('company'), 'marklogic'))

The following query returns the documents which have an element named "company" - cts:element-value-query( xs:QName('company'), '*', ("wildcarded"))) The following query returns the documents which have an element named "company" with an attribute named "name&...