How to use C# Comments ???
Hello everyone, I hope you all are fine and having fun. Today's tutorial is a quick one and is about how to use C# Comments. Comment is an important part of any programming language, although its not a directly part but they indirectly help a lot especially in complex projects.
I have also shared a tutorial on How to use comments in c++, you should read that post as well because I have explained few basic concepts in it. You guys are also welcome to give us feedback about this new C# tutorial series. If you have any suggestions about it then do let us know in comments.
How to use C# Comments ???
- Comments are simple documented text lines, completely ignored by the compiler and are used to explain or provide any additional information about coding.
- There are 3 types of comments available in C#, which are:
- Single Line Comments. ( Symbol used: // )
- Multi-Line Comments. ( Initial Symbol: /* Closing Symbol */ )
- XML Documentation Comments. ( /// )
- Now, let's have have look at each one of them in detail:
Single Line Comments
- Single Line Comments are used to comment any text in a single line, we have to place two forward slashes ( // ) and everything after that will be ignored by the compiler.
- Let's have a look at How to use Single Line Comments, in below figure:
- You can see in above figure, that I have used green comments above each block to explain my code i.e. mentioning 2D & 3D arrays, accessing array elements etc.
- Moreover, I have also used comments in front of the line i.e. displaying data at location 0, 0 etc. In this case, I am just explaining a single line.
Multi-Line Comments in C#
- We can also comment out multiple lines by using /* */ these symbols.
- Let's say, you don't want to execute some part of your code i.e. 100 lines, then it would be too difficult to place // these symbols in front of each line.
- In such cases, there's a need for Multi-Line Comments, here's an example:
- At the top of above code, you can see I have used Multi-Line Comments to give a simple introduction, here you can also add description of your project/code.
- Moreover, I have also commented out Console code, I just want output using For Loop and I have used Multi-Line Comments for that.
XML Documentation Comments
- In Microsoft Visual Studio, when you hover your cursor on any object then it pops up an info box.
- If you want to add any information in this pop up box then you need to use XML Documentation Comments, as shown in below figure:
- In the above code, I have created a new class named TEPClass, we will discuss classes later in detail, but for now just focus on XML comment above that class.
- In Program class, I have called TEPClass and now when I hover my cursor over it, you can see a pop up box appeared and it has that XML comment in it.
- I have placed a red arrow in front of it, here we can place a short description of our class.
Why we need to use C# comments ???
- Let's say you have to use some old code which you have designed a year ago.
- Now when you read your own code after a year, it will be difficult to understand.
- But if you have placed some check note (comments) for each command then you can easily understand it.
That's all for C# comments. I hope you guys have understood how & why we need to use C# Comments. In next tutorial, we will have a look at How to use If Loop in C#.
How to use C# String Variables
Hello friends, I hope you all are fine and having fun with your lives. In today's tutorial, we are gonna have a look at How to use C# String Variables in your C# Projects. In the previous tutorials, we have a look at How to use C# Int Variables and also have seen How to use C# Double Variable. So, now today we are gonna see how to use C# String Variable.
We have already discussed the variables in detail so I hope that you must have the idea of what variables are and if you don't then you must read the previous tutorials first. The code is also given below in the tutorial. So, let's get started with How to use C# String Variables:
How to use C# String Variables ???
- C# also supports string variable, a string variable can save anything in it in the form of characters.
- C# String variable can be of any length.
- So, let's design a small code to show how C# String works.
- First of all design a simple C# Project and add one button and one text box in it, as shown in below figure:
- Now change the Text of your Button to Click Here and Name of the button to ClickHere.
- Similarly change the Name of the text box to txtClick.
- We have already designed a similar project in How to use C# Int variables.
- Now that our project is added so now add the below code into it an your code will look something like:
- Now you can see in the above figure, that first I have created a string variable named webBlog.
- After that I have assigned it a value, because the variable is a C# string variable that's why it can save this string easily in it.
- After that I have simply displayed it in that text box.
- You must have noticed that this time we didn't have converted the value to string as we did in C# Double variable.
- Because our variable is already a string.
- Here's the complete code for copying:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Variables
{
public partial class Form1 : Form
{
string webBlog;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void ClickHere_Click(object sender, EventArgs e)
{
webBlog = "www.TheEngineeringProjects.com";
txtClick.Text = webBlog;
}
}
}
- Now let's have a look at the results.
- So, run your project and then click on the button and the string will appear in the text box as shown in below figure:
- So that's how C# string variable works.
- Now you can save any kind of long strings in C# string variable.
- Now let's have a look at few of the string properties.
C# String Comparing
- Suppose you have two strings then How to compare them.
- So write your code as shown in below figure:
- Now you can see in the above code, I have used two C# String variables webBlog1 and webBlog2.
- I have given the same text to both of these C# string variables.
- Now after that I have used a small function called String.Compare() and it takes two C# string variables.
- After that it compares these two C# string variables and if they are same then it give 0 so that's why I have compared it to 0 means if the two C# string are equal then I have printed Both are equal otherwise not equal.
- So, that's how you can compare two C# String Variables.
- Here's the code for copy:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Variables
{
public partial class Form1 : Form
{
string webBlog1, webBlog2;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void ClickHere_Click(object sender, EventArgs e)
{
webBlog1 = "www.TheEngineeringProjects.com";
webBlog2 = "www.TheEngineeringProjects.com";
if (String.Compare(webBlog1, webBlog2) == 0)
{
txtClick.Text = "Both are equal";
}
else
{
txtClick.Text = "Both are not equal";
}
}
}
}
Find subString in C# String
- Now suppose you have a long string and you want to find some small string whether its in the long string or not.
- Then you can use another function named as contain and the below example shows how to use this command:
- In the above figure, you can see that I have initialized a C# String variable and given it a string text.
- After that I have used the function String.Contain and checked a part in the string.
- So you can see the String is actually in the main string so it will give Its present in the string otherwise not present.
- So, run your project and then click the button and you will get something as shown in below figure:
- Now, you can see it has given that its present in the string.
- Here's the code for copying:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Variables
{
public partial class Form1 : Form
{
string webBlog1, webBlog2;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void ClickHere_Click(object sender, EventArgs e)
{
webBlog1 = "www.TheEngineeringProjects.com";
if (webBlog1.Contains("Projects"))
{
txtClick.Text = "Its present in string";
}
else
{
txtClick.Text = "Its not present in string.";
}
}
}
}
Dividing a C# String
- So, now let's get something out of a string.
- Suppose in some project you have a very long C# string and you just want a part of that C# string.
- Then what you need to use is another string command which is webBlog1.Substring(4).
- So, have a look at the below code:
- Now in the above code you can see I have initialized a C# String variable and assigned it a value.
- After that, I have used second variable and then I have subString it by four characters and now run your project and click the button and you will get results as shown in below figure:
- So, you can see in the above string I have subString four characters in the initials and then the remaining is shown in the text box.
- So, that's how you can take any number of subString from the C# String.
So, that's all about C# String Variable. I hope you guys have learned something out of it. that's all for today. In the next tutorial we will learn more about C#. Till then take care and have fun !!! :)