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C# Hello World! 

C# Hello World! 



Click on RUN button to see the output

C Sharp Online Compiler

Write, Run & Share C# code online using OneCompiler's C# online compiler for free. It's one of the robust, feature-rich online compilers for C# language, running on the latest version 8.0. Getting started with the OneCompiler's C# compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C#. OneCompiler also has reference programs, where you can look for the sample programs and start learning. Happy learning!!

Read inputs from stdin

OneCompiler's C# online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

using System;
namespace Sample
  class Test
      public static void Main(string[] args)
         string name;
         name = Console.ReadLine();
         Console.WriteLine("Hello {0} ", name);

About C Sharp

C# is a general purpose object-oriented programming language by Microsoft. Though initially it was developed as part of .net but later it was approved by ECMA and ISO standards.

You can use C# to create variety of applications, like web, windows, mobile, console applications and much more using Visual studio.

Syntax help

Data types

Data TypeDescriptionRangesize
intTo store integers-2,147,483,648 to 2,147,483,6474 bytes
doubleto store large floating point numbers with decimalscan store 15 decimal digits8 bytes
floatto store floating point numbers with decimalscan store upto 7 decimal digits4 bytes
charto store single characters-2 bytes
stringto stores text-2 bytes per character
boolto stores either true or false-1 bit



datatype variable-name = value;


1. If-Else:

When ever you want to perform a set of operations based on a condition or set of few conditions IF-ELSE is used.

if(conditional-expression) {
   // code
else {
   // code

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression) {    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
 // code to be executed when all the above cases are not matched;    

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement) {
  // code  

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of ierations is not known in advance.

while(condition) {
 // code 

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {
  // code 
} while (condition);


Array is a collection of similar data which is stored in continuous memory addresses. Array values can be fetched using index. Index starts from 0 to size-1.


data-type[] array-name;


Method is a set of statements which gets executed only when they are called. Call the method name in the main function to execute the method.


static void method-name() 
  // code to be executed

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Reference Programs:


No tags available for C#

How to use?

Choose the language in which you want to run your program, by clicking the button next to Run. And then write your code in the code box, You can use the auto complete snippets and warnings and errors which helps you to write better code faster way.
Once you are done writing your code click the Run button, now the code will be submitted to OneCompiler and you will see the results in a second.

How to contribute?

Please fork OneCompiler repository and contribute us by adding more languages or the features to the existing OneCompiler backend.
You can also contibute to the community by adding more programs which users can search and use as base code for their programs.

API & More

You can embed OneCompiler into your own website. That helps your website users to write and test their programs within your website.
If you want to run and see the results from your backend you can utilize the OneCompiler API by integrating it with your backend.