Tutorial by Examples: d

In this example, a destructor is explicitly invoked for an object that will later be automatically destroyed. struct S { ~S() { std::cout << "destroying S\n"; } }; int main() { S s; s.~S(); } // UB: s destroyed a second time here A similar issue occurs when a st...

Creating a list of KeyValuePair: Dictionary<int, int> dictionary = new Dictionary<int, int>(); List<KeyValuePair<int, int>> list = new List<KeyValuePair<int, int>>(); list.AddRange(dictionary); Creating a list of keys: Dictionary<int, int> dictionary ...

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, ...

Having example type like this: public TestClass { public static string StaticPublicField = "StaticPublicFieldValue"; } We can retrieve value of StaticPublicField: var fieldExpr = Expression.Field(null, typeof(TestClass), "StaticPublicField"); var labmda = Expression....

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 ...

Basic Error Handling By default, Express will look for an 'error' view in the /views directory to render. Simply create the 'error' view and place it in the views directory to handle errors. Errors are written with the error message, status and stack trace, for example: views/error.pug html bo...

The canonical way of writing code inside documentation is with the {@code } construct. If you have multiline code wrap inside <pre></pre>. /** * The Class TestUtils. * <p> * This is an {@code inline("code example")}. * <p> * You should wrap it in pre tags...

Newtonsoft's Json.NET allows you to bind json dynamically (using ExpandoObject / Dynamic objects) without the need to create the type explicitly. Serialization dynamic jsonObject = new ExpandoObject(); jsonObject.Title = "Merchent of Venice"; jsonObject.Author = "William Shakes...

This command has several related yet distinct forms. del v If v is a variable, the command del v removes the variable from its scope. For example: x = 5 print(x) # out: 5 del x print(x) # NameError: name 'f' is not defined Note that del is a binding occurence, which means that unless expl...

This simple example shows how to start multiple threads in Java. Note that the threads are not guaranteed to execute in order, and the execution ordering may vary for each run. public class HelloMultithreading { public static void main(String[] args) { for (int i = 0; i < 10; i...

We can create a better mapper classes with extension methods, Suppose if i have some DTO classes like public class UserDTO { public AddressDTO Address { get; set; } } public class AddressDTO { public string Name { get; set; } } and i need to map to corresponding v...

cts:search( fn:doc(), cts:word-query("marklogic"))

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&...

The example is for illustration purpose of using libraries and helpers and not a valid code. Do not copy / paste it on your projects. HELPER helpers/sendEmail_helper.php if ( ! function_exists('sendEmail')) { function sendEmail($email, $subject, $message, $lang, $cc = null, $file = null) { ...