barcode vb.net 2013 FUNCTIONS AND SCRIPTS in C#.NET

Making Code 39 Full ASCII in C#.NET FUNCTIONS AND SCRIPTS

FUNCTIONS AND SCRIPTS
Code39 Creation In C#.NET
Using Barcode creation for VS .NET Control to generate, create Code 39 Full ASCII image in Visual Studio .NET applications.
www.OnBarcode.com
Code 3 Of 9 Reader In C#.NET
Using Barcode decoder for VS .NET Control to read, scan read, scan image in Visual Studio .NET applications.
www.OnBarcode.com
AUTHOR S NOTE
Drawing EAN / UCC - 14 In Visual C#.NET
Using Barcode drawer for .NET Control to generate, create GTIN - 128 image in Visual Studio .NET applications.
www.OnBarcode.com
UPC A Printer In Visual C#.NET
Using Barcode encoder for VS .NET Control to generate, create UPC Code image in .NET framework applications.
www.OnBarcode.com
The terminology used here comes from UNIX shells. Depending on your regional background, you may consider the correct term to be, variously, dotting , sourcing , or dot sourcing . It s entertaining to see regional terminology even within a single technology community. In fact, this is very reminiscent of The Great Pop vs. Soda Controversy . In the United States, people refer to soft drinks as pop , soda , or soda pop , depending on what part of the country they come from. This latter phenomenon is (startlingly) well documented at http://www.popvssoda.com.
Make ANSI/AIM Code 39 In Visual C#.NET
Using Barcode encoder for Visual Studio .NET Control to generate, create Code 3/9 image in Visual Studio .NET applications.
www.OnBarcode.com
2D Maker In C#
Using Barcode creation for Visual Studio .NET Control to generate, create Matrix image in .NET applications.
www.OnBarcode.com
As we ve discussed, we usually only care about the results of a function and want all of the intermediate variables and so on discarded when the script or function exits. This is why scripts and functions get their own scope. But sometimes you do care about all of the intermediate by-products. This is typically the case when you want to create a library of functions or variable definitions. In this situation, you want the script to run in the current scope.
Code 128 Code Set C Drawer In C#.NET
Using Barcode drawer for Visual Studio .NET Control to generate, create USS Code 128 image in VS .NET applications.
www.OnBarcode.com
4-State Customer Barcode Generator In Visual C#.NET
Using Barcode maker for Visual Studio .NET Control to generate, create 4-State Customer Barcode image in Visual Studio .NET applications.
www.OnBarcode.com
AUTHOR S NOTE
Code 3/9 Maker In None
Using Barcode creation for Office Word Control to generate, create Code39 image in Office Word applications.
www.OnBarcode.com
ANSI/AIM Code 39 Printer In VB.NET
Using Barcode generation for .NET framework Control to generate, create Code 3/9 image in VS .NET applications.
www.OnBarcode.com
This is how cmd.exe works by default, as this example shows. We have a cmd file foo.cmd
European Article Number 13 Generation In None
Using Barcode encoder for Online Control to generate, create GS1 - 13 image in Online applications.
www.OnBarcode.com
Barcode Creator In Objective-C
Using Barcode printer for iPhone Control to generate, create Barcode image in iPhone applications.
www.OnBarcode.com
C:\files>type foo.cmd set a=4
Draw UPC Code In Java
Using Barcode encoder for BIRT reports Control to generate, create UPC Code image in BIRT reports applications.
www.OnBarcode.com
PDF-417 2d Barcode Reader In Visual C#
Using Barcode scanner for VS .NET Control to read, scan read, scan image in .NET framework applications.
www.OnBarcode.com
now set a variable a to 1 and display it:
Encode UCC - 12 In None
Using Barcode drawer for Online Control to generate, create UPC A image in Online applications.
www.OnBarcode.com
Draw Barcode In Objective-C
Using Barcode printer for iPhone Control to generate, create Barcode image in iPhone applications.
www.OnBarcode.com
C:\files>set a=1 C:\files>echo %a% 1
Data Matrix 2d Barcode Creation In VB.NET
Using Barcode creator for Visual Studio .NET Control to generate, create ECC200 image in .NET framework applications.
www.OnBarcode.com
Barcode Creation In Objective-C
Using Barcode encoder for iPad Control to generate, create Barcode image in iPad applications.
www.OnBarcode.com
Next run the cmd file
UCC - 12 Maker In Java
Using Barcode generation for Java Control to generate, create GTIN - 12 image in Java applications.
www.OnBarcode.com
Painting Quick Response Code In None
Using Barcode creator for Office Excel Control to generate, create QR Code image in Excel applications.
www.OnBarcode.com
C:\files>foo C:\files>set a=4
and we see that the variable has been changed.
C:\files>echo %a% 4
As a consequence of this behavior, it s common to have cmd files that do nothing but set a bunch of variables. To do this in PowerShell, you would dot the script.
So how do you dot a script By putting a dot or period in front of the name when you execute it. Note that there has to be a space between the dot and the name, otherwise it will be considered part of the name. Let s look at an example. First we create a script that sets $x to 22.
PS >> >> >> >> (5) > @' "Setting x to 22" $x = 22 '@ > my-script.ps1
SCRIPTS AT LONG LAST
and we ll test it. First set $x to a known value
PS (6) > $x=3 PS (7) > $x 3
then run the script as we would normally:
PS (8) > ./my-script Setting x to 22
Checking $x, we see that it is (correctly) unchanged.
PS (9) > $x 3
Now we ll dot the script.
PS (10) > . ./my-script Setting x to 22 PS (11) > $x 22
This time $x is changed. What follows the . isn t limited to a simple file name. It could be a variable or expression, as was the case with & :
PS (12) > $name = "./my-script" PS (13) > . $name Setting x to 22
The last thing to note is that dotting works for both scripts and functions. Let s define a function to show this:
PS (17) > function set-x ($x) {$x = $x} PS (18) > . set-x 3 PS (19) > $x 3
In this example, we define the function set-x and dot it, passing in the value 3. The result is that the global variable $x is set to 3.
SUMMARY
This chapter finally introduced scripting and programming in general in PowerShell. While there was a lot of material, the following are the key points: PowerShell programming can be done either with functions or scripts. Functions are created using the function keyword, whereas scripts are simply pieces of PowerShell script text stored in a file. In PowerShell, scripts and functions are closely related. The same principles and techniques apply to both.
FUNCTIONS AND SCRIPTS
Parameters can be specified for functions either immediately after the function keyword or in the body of the function using the param keyword. In scripts, only the param keyword can be used. PowerShell uses dynamic scoping for variables. You can modify how a variable name is resolved by using the scope modifiers in the variable names. Functions and scripts stream their output. In other words, they return the results of every statement executed as though it were written to the output stream. This feature means that you almost never have to write your own code to accumulate results. Because of the differences between how functions work in PowerShell and how they work in more conventional languages, you may receive some unexpected results when creating your functions, so you picked up some tips on debugging these problems. Functions can be used as simple functions, filters, or as full-fledged cmdlets. The function drive is used to manage the functions defined in your session. This means that you use the same commands you use for managing files to manage functions. Even though we covered a lot of material in this chapter, we ve really only covered the surface aspects of programming with PowerShell. In chapter 8, we ll cover scriptblocks, which are the objects underlying the infrastructure for scripts and functions. We ll talk about how you can use these scriptblocks to extend the PowerShell language, extend existing objects, and even create your own objects.
Copyright © OnBarcode.com . All rights reserved.