Extension methods can be used for writing strongly typed wrappers for dictionary-like objects. For example a cache, HttpContext.Items at cetera...
public static class CacheExtensions
{
public static void SetUserInfo(this Cache cache, UserInfo data) =>
cache["UserInfo"] ...
In order to enable EdgeCache, set the following HTTP response headers (Do not deviate from this exact format):
Cache-Control header to public, max-age=X where:
X = the number of seconds that you want the response to be cached for
X > 60 seconds
X < 365*24*60*60
Set the Pragma he...
You can also receive regular updates of the user's location; for example, as they move around while using a mobile device. Location tracking over time can be very sensitive, so be sure to explain to the user ahead of time why you're requesting this permission and how you'll use the data.
if (naviga...
MySQL3.19
DROP TABLE IF EXISTS MyTable;
PostgreSQL8.x
DROP TABLE IF EXISTS MyTable;
SQL Server2005
If Exists(Select * From Information_Schema.Tables
Where Table_Schema = 'dbo'
And Table_Name = 'MyTable')
Drop Table dbo.MyTable
SQLite3.0
DROP TABLE IF EXI...
Sometimes, programmers who are new Java will use primitive types and wrappers interchangeably. This can lead to problems. Consider this example:
public class MyRecord {
public int a, b;
public Integer c, d;
}
...
MyRecord record = new MyRecord();
record.a = 1; // OK
...
Use this option if you don't need an Application subclass.
This is the simplest option, but this way you can't provide your own Application subclass. If an Application subclass is needed, you will have to switch to one of the other options to do so.
For this option, simply specify the fully-quali...
Use this option if your project requires an Application subclass.
Specify this Application subclass using the android:name property in the manifest file inside the application tag.
In the Application subclass, add the attachBaseContext() method override, and in that method call MultiDex.install():...
If a sentence contains computer code (for example, the name of an HTML element), use the code element to mark it up:
<p>The <code>a</code> element creates a hyperlink.</p>
If the formatting (white space, new lines, indentation) of the code matters, use the pre element in combination with the code element:
<pre>
<code>
x = 42
if x == 42:
print "x is … … 42"
</code>
</pre>
You still have to esc...
Example Using Activity w/ LocationRequest
/*
* This example is useful if you only want to receive updates in this
* activity only, and have no use for location anywhere else.
*/
public class LocationActivity extends AppCompatActivity implements
GoogleApiClient.ConnectionCallbacks, ...
Data Model
public class Item {
private String name;
public String getName() {
return name;
}
public void setName(String name){
this.name = name;
}
}
Layout XML
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:an...
SELECT
s.name + '.' + t.NAME AS TableName,
SUM(a.used_pages)*8 AS 'TableSizeKB' --a page in SQL Server is 8kb
FROM sys.tables t
JOIN sys.schemas s on t.schema_id = s.schema_id
LEFT JOIN sys.indexes i ON t.OBJECT_ID = i.object_id
LEFT JOIN sys.partitions p ON i.object_id = ...
Optional Parameters
In TypeScript, every parameter is assumed to be required by the function. You can add a ? at the end of a parameter name to set it as optional.
For example, the lastName parameter of this function is optional:
function buildName(firstName: string, lastName?: string) {
// ...
You can customize your theme’s color palette.
Using framework APIs
5.0
<style name="AppTheme" parent="Theme.Material">
<item name="android:colorPrimary">@color/primary</item>
<item name="android:colorPrimaryDark">@color/pri...
XML elements often nest, have data in attributes and/or as character data. The way to capture this data is by using ,attr and ,chardata respectively for those cases.
var doc = `
<parent>
<child1 attr1="attribute one"/>
<child2>and some cdata</child2>
</p...
Pointer Methods
Pointer methods can be called even if the variable is itself not a pointer.
According to the Go Spec,
. . . a reference to a non-interface method with a pointer receiver using an addressable value will automatically take the address of that value: t.Mp is equivalent to (&t)....
The primary task of the manifest is to inform the system about the app's components. For example, a manifest file can declare an activity as follows:
<?xml version="1.0" encoding="utf-8"?>
<manifest ... >
<application android:icon="@drawable/app_icon.pn...
