- Mac Run App From Command Line With Arguments Free
- Mac Run App From Command Line With Arguments Using
- Mac Run App From Command Line With Arguments Mac
- Mac Run App From Command Line With Arguments Windows 10
The following should let you specify command-line arguments for the.app itself: Right click.app bundle, select 'Show Package Contents', navigate to Info.plist, double click it, find Args key, edit. I don't have an OS X machine handy right at the moment, so I can't check whether you could also do this to an alias (if you wanted to keep the. Command-line arguments for the Source Dedicated Server executable (srcds.exe, srcdsrun) Command-line parameters-allowdebug (Same as -debug?)-autoupdate Autoupdate the game. Requires -steamdir and -steamcmdscript to be set (Linux/Unix only).-binary Use the specified binary (no auto detection) (Linux/Unix only).-console. You will type commands in an application called the Terminal. Open a terminal window. You can find this under Go - Applications - Utilities. Drag the Terminal to your dock since you will be using it frequently. You should now have a Terminal window somewhere on the screen. It will have a prompt that looks something like: machine: wayne$.
But for older versions of Mac OS X, and because app bundles aren't designed to be passed command line arguments, the conventional mechanism is to use Apple Events for files like here for Cocoa apps or here for Carbon apps. You could also probably do something kludgey by passing parameters in using environment variables. In this Command Line Programs on macOS tutorial, you will write a command-line utilty named Panagram. Depending on the options passed in, it will detect if a given input is a palindrome or anagram. It can be started with predefined arguments, or run in interactive mode where the user is prompted to enter the required values.
-->The Main
method is the entry point of a C# application. (Libraries and services do not require a Main
method as an entry point.) When the application is started, the Main
method is the first method that is invoked.
There can only be one entry point in a C# program. If you have more than one class that has a Main
method, you must compile your program with the StartupObject compiler option to specify which Main
method to use as the entry point. For more information, see StartupObject (C# Compiler Options).
Starting in C# 9, you can omit the Main
method, and write C# statements as if they were in the Main
method, as in the following example:
For information about how to write application code with an implicit entry point method, see Top-level statements.
Overview
- The
Main
method is the entry point of an executable program; it is where the program control starts and ends. Main
is declared inside a class or struct.Main
must bestatic
and it need not bepublic
. (In the earlier example, it receives the default access ofprivate
.) The enclosing class or struct is not required to be static.Main
can either have avoid
,int
, or, starting with C# 7.1,Task
, orTask<int>
return type.- If and only if
Main
returns aTask
orTask<int>
, the declaration ofMain
may include theasync
modifier. This specifically excludes anasync void Main
method. - The
Main
method can be declared with or without astring[]
parameter that contains command-line arguments. When using Visual Studio to create Windows applications, you can add the parameter manually or else use the GetCommandLineArgs() method to obtain the command-line arguments. Parameters are read as zero-indexed command-line arguments. Unlike C and C++, the name of the program is not treated as the first command-line argument in theargs
array, but it is the first element of the GetCommandLineArgs() method.
The following list shows valid Main
signatures:
The preceding examples all use the public
accessor modifier. That's typical, but not required.
The addition of async
and Task
, Task<int>
return types simplifies program code when console applications need to start and await
asynchronous operations in Main
.
Main() return values
You can return an int
from the Main
method by defining the method in one of the following ways:
Main method code | Main signature |
---|---|
No use of args or await | static int Main() |
Uses args , no use of await | static int Main(string[] args) |
No use of args , uses await | static async Task<int> Main() |
Uses args and await | static async Task<int> Main(string[] args) |
If the return value from Main
is not used, returning void
or Task
allows for slightly simpler code.
Main method code | Main signature |
---|---|
No use of args or await | static void Main() |
Uses args , no use of await | static void Main(string[] args) |
No use of args , uses await | static async Task Main() |
Uses args and await | static async Task Main(string[] args) |
However, returning int
or Task<int>
enables the program to communicate status information to other programs or scripts that invoke the executable file.
The following example shows how the exit code for the process can be accessed.
This example uses .NET Core command-line tools. If you are unfamiliar with .NET Core command-line tools, you can learn about them in this get-started article.
Create a new application by running dotnet new console
. Modify the Main
method in Program.cs as follows:
When a program is executed in Windows, any value returned from the Main
function is stored in an environment variable. This environment variable can be retrieved using ERRORLEVEL
from a batch file, or $LastExitCode
from PowerShell.
You can build the application using the dotnet CLIdotnet build
command.
Next, create a PowerShell script to run the application and display the result. Paste the following code into a text file and save it as test.ps1
in the folder that contains the project. Run the PowerShell script by typing test.ps1
at the PowerShell prompt.
Because the code returns zero, the batch file will report success. However, if you change MainReturnValTest.cs to return a non-zero value and then recompile the program, subsequent execution of the PowerShell script will report failure.
Async Main return values
When you declare an async
return value for Main
, the compiler generates the boilerplate code for calling asynchronous methods in Main
. If you don't specify the async
keyword, you need to write that code yourself, as shown in the following example. The code in the example ensures that your program runs until the asynchronous operation is completed:
This boilerplate code can be replaced by:
An advantage of declaring Main
as async
is that the compiler always generates the correct code.
When the application entry point returns a Task
or Task<int>
, the compiler generates a new entry point that calls the entry point method declared in the application code. Assuming that this entry point is called $GeneratedMain
, the compiler generates the following code for these entry points:
static Task Main()
results in the compiler emitting the equivalent ofprivate static void $GeneratedMain() => Main().GetAwaiter().GetResult();
static Task Main(string[])
results in the compiler emitting the equivalent ofprivate static void $GeneratedMain(string[] args) => Main(args).GetAwaiter().GetResult();
static Task<int> Main()
results in the compiler emitting the equivalent ofprivate static int $GeneratedMain() => Main().GetAwaiter().GetResult();
static Task<int> Main(string[])
results in the compiler emitting the equivalent ofprivate static int $GeneratedMain(string[] args) => Main(args).GetAwaiter().GetResult();
Note
If the examples used async
modifier on the Main
method, the compiler would generate the same code.
Command-Line Arguments
You can send arguments to the Main
method by defining the method in one of the following ways:
Mac Run App From Command Line With Arguments Free
Main method code | Main signature |
---|---|
No return value, no use of await | static void Main(string[] args) |
Return value, no use of await | static int Main(string[] args) |
No return value, uses await | static async Task Main(string[] args) |
Return value, uses await | static async Task<int> Main(string[] args) |
If the arguments are not used, you can omit args
from the method signature for slightly simpler code:
Main method code | Main signature |
---|---|
No return value, no use of await | static void Main() |
Return value, no use of await | static int Main() |
No return value, uses await | static async Task Main() |
Return value, uses await | static async Task<int> Main() |
Note
You can also use Environment.CommandLine or Environment.GetCommandLineArgs to access the command-line arguments from any point in a console or Windows Forms application. To enable command-line arguments in the Main
method signature in a Windows Forms application, you must manually modify the signature of Main
. The code generated by the Windows Forms designer creates Main
without an input parameter.
The parameter of the Main
method is a String array that represents the command-line arguments. Usually you determine whether arguments exist by testing the Length
property, for example:
Tip
The args
array can't be null. So, it's safe to access the Length
property without null checking.
You can also convert the string arguments to numeric types by using the Convert class or the Parse
method. For example, the following statement converts the string
to a long
number by using the Parse method:
Mac Run App From Command Line With Arguments Using
It is also possible to use the C# type long
, which aliases Int64
:
You can also use the Convert
class method ToInt64
to do the same thing:
For more information, see Parse and Convert.
The following example shows how to use command-line arguments in a console application. The application takes one argument at run time, converts the argument to an integer, and calculates the factorial of the number. If no arguments are supplied, the application issues a message that explains the correct usage of the program.
To compile and run the application from a command prompt, follow these steps:
Paste the following code into any text editor, and then save the file as a text file with the name Factorial.cs.
From the Start screen or Start menu, open a Visual Studio Developer Command Prompt window, and then navigate to the folder that contains the file that you created.
Enter the following command to compile the application.
dotnet build
If your application has no compilation errors, an executable file that's named Factorial.exe is created.
Enter the following command to calculate the factorial of 3:
dotnet run -- 3
The command produces this output:
The factorial of 3 is 6.
Note
When running an application in Visual Studio, you can specify command-line arguments in the Debug Page, Project Designer.
Mac Run App From Command Line With Arguments Mac
C# language specification
Mac Run App From Command Line With Arguments Windows 10
For more information, see the C# Language Specification. The language specification is the definitive source for C# syntax and usage.