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Dim Value As Variant 'Explicit Dim Value 'Implicit A Variant is a COM data type that is used for storing and exchanging values of arbitrary types, and any other type in VBA can be assigned to a Variant. Variables declared without an explicit type specified by As [Type] default t...

Dim Value As LongPtr The LongPtr was introduced into VBA in order to support 64 bit platforms. On a 32 bit system, it is treated as a Long and on 64 bit systems it is treated as a LongLong. It's primary use is in providing a portable way to store and pass pointers on both architectures (See Chan...

To define a new middleware we have to create the middleware class: class AuthenticationMiddleware { //this method will execute when the middleware will be triggered public function handle ( $request, Closure $next ) { if ( ! Auth::user() ) { return red...

Callbacks can be used to provide code to be executed after a method has completed: /** * @arg {Function} then continuation callback */ function doSomething(then) { console.log('Doing something'); then(); } // Do something, then execute callback to log 'done' doSomething(function () ...

Callbacks are often used to provide error handling. This is a form of control flow branching, where some instructions are executed only when an error occurs: const expected = true; function compare(actual, success, failure) { if (actual === expected) { success(); } else { failure...

If you want to delete rows (or columns) in a loop, you should always loop starting from the end of range and move back in every step. In case of using the code: Dim i As Long With Workbooks("Book1").Worksheets("Sheet1") For i = 1 To 4 If IsEmpty(.Cells(i, 1)) Then...

#Modules to use use Cwd 'abs_path'; use Win32::OLE; use Win32::OLE qw(in with); use Win32::OLE::Const "Microsoft Excel"; $Win32::OLE::Warn = 3; #Need to use absolute path for Excel files my $excel_file = abs_path("$Excel_path") or die "Error: the file $Excel_path ha...

#Get the active Worksheet my $Book = $Excel->Activewindow; my $Sheet = $Book->Activesheet; #List of Worksheet names my @list_Sheet = map { $_->{'Name'} } (in $Book->{Worksheets}); #Access a given Worksheet my $Sheet = $Book->Worksheets($list_Sheet[0]); #Add new Worksheet...

#Edit the value of a cell (2 methods) $Sheet->Range("A1")->{Value} = 1234; $Sheet->Cells(1,1)->{Value} = 1234; #Edit the values in a range of cells $Sheet->Range("A8:C9")->{Value} = [[ undef, 'Xyzzy', 'Plugh' ], [ 42, 'Pe...

#Insert a row before/after line 22 $Sheet->Rows("22:22")->Insert(xlUp, xlFormatFromRightOrBelow); $Sheet->Rows("23:23")->Insert(-4121,0); #xlDown is -4121 and that xlFormatFromLeftOrAbove is 0 #Delete a row $Sheet->Rows("22:22")->Delete(); ...

In ui-router a state can hold multiple views, each with his own controller and a template .state('dashboard', { name: 'dashboard', url: '/dashboard', views: { "view1": { templateUrl: "path/to/view1.html", controller: "...

You can resolve data into your state when you transition into it, usually it's useful when the state needs to use that data, or to resolve into a state when some provided input needs to be authenticated. When you define your states, you will need to provide a map of values to be resolved into the ....

The syntax for filtering for NULL (i.e. the absence of a value) in WHERE blocks is slightly different than filtering for specific values. SELECT * FROM Employees WHERE ManagerId IS NULL ; SELECT * FROM Employees WHERE ManagerId IS NOT NULL ; Note that because NULL is not equal to anything, not ...

When creating tables it is possible to declare a column as nullable or non-nullable. CREATE TABLE MyTable ( MyCol1 INT NOT NULL, -- non-nullable MyCol2 INT NULL -- nullable ) ; By default every column (except those in primary key constraint) is nullable unless we explicitly set ...

Setting a field to NULL works exactly like with any other value: UPDATE Employees SET ManagerId = NULL WHERE Id = 4

For example inserting an employee with no phone number and no manager into the Employees example table: INSERT INTO Employees (Id, FName, LName, PhoneNumber, ManagerId, DepartmentId, Salary, HireDate) VALUES (5, 'Jane', 'Doe', NULL, NULL, 2, 800, '2016-07-22') ;

To customize appearance of all instances of a class, access appearance proxy of the desired class. For example: Set UIButton tint color Swift: UIButton.appearance().tintColor = UIColor.greenColor() Objective-C: [UIButton appearance].tintColor = [UIColor greenColor]; Set UIButton background...

Use appearanceWhenContainedInInstancesOfClasses: to customize the appearance for instance of a class when contained within an instance of container class. For example customization of UILabel's textColor and backgroundColor within ViewController class will look like this: Set UILabel text color Sw...

A cross-origin request must be sent including the Origin header. This indicates from where the request originated. For example, a cross-origin request from http://example.com to http://example.org would look like this: GET /cors HTTP/1.1 Host: example.org Origin: example.com The server will us...

The response to a CORS request must include an Access-Control-Allow-Origin header, which dictates what origins are allowed to use the CORS resource. This header can take one of three values: An origin. Doing this permits requests from that origin only. The character *. This permits requests from...