js if boolean : how to use?

Posted under javascript sample code On By mohammed.mutawe

js if boolean

js if boolean is one of the most related things in machine language and it contains a clear abbreviation in the number of code words to appear as either true or false without using JavaScript operators and in this lesson we will create simple variables that help you understand logical and singular signs in short.

Perhaps this type of js condition does not need a very big explanation and all you have to do is wait for two results True or False and these two words are reserved words in javascript and do not need quotes to activate it can also express js if boolean by the numbers 1 and 0 and the number 1 indicates On True and 0 is expressed as False.

 

Why Boolean?

The use of Boolean dates back to the mathematician George Boole, and it is a series of logical operations that are used in complex electrical circuits and was derived in programming languages ​​to indicate the actual access to the machine language and the choice of only one of the two possibilities that express a value achieved during the condition and the procedure is completed based on it.

In fact, js if boolean is a conditional use of regular conditional sentences, but if we go back to the basics of programming languages, we will find that Boolean is Variable like other variables, but it differs in restricting its freedom without the variables Int, String or Float, as it is not functionally similar to it, but rather it holds a page Only variables in the definition.

The benefit of using js if boolean is the following:

  • Reduce the number of words in the code.
  • Good programmatic organization.
  • Integration in machine language and production of high quality code.

 

Boolean in variables

Well, after we have defined what is js if boolean, or we have defined and explained a Boolean, we will now define the first variable with a null value, let it be as follows:

<script>
var online = null;
</script>

Note that I declared a variable of type Bool, but how do we know that? , In defining JavaScript variables, we cannot distinguish between some of them except in the added value. For example, what showed me the type and nature of the variable is the word null reserved in this language, which enabled me to know that this variable must be of type Bool.

If I enable this variable, I will do the following:

<script>
online = true;
</script>

I have a Boolean variable activated from JS , Online has been switched to true , which enabled me to take advantage of it. If I want to deactivate this variable, I will do the following:

<script>
 online = false;
</script>

I think the idea is good for you now that you know how to use Boolean as required and now I will make a simple code for you so that the idea becomes easy for you little by little.

<script>
var online = false;

for(var i= 0 ; i<10 ; i++){

if(i==2){
online = true;
if(online){document.write("You are online!");}
}


}
</script>

Boolean is not very different in programming languages. It provides a unified method for building variables and relying on them to manage functions. Through these variables, you will produce light and optimized code, and you will exploit the browser’s resources very well, as there are some codes that you do not want to work at the same time, which hinders Display the page at the desired speed.

 

Js if Boolean

Relying on Js if Boolean is something you may need later, but I don’t use the reserved word Boolean much because I can reach the result without mentioning it in conditional sentences, but it’s worth a try sometimes, maybe there are certain circumstances that will force you to use it.

<script>

if(Boolean(9 < 50))
{
document.write("9 is smaller than 50!");
}
</script>

 

There are some ways that you will use to check whether a variable contains a value or not, which is an undefined value. Imagine with me that you connect to a database and fetch a value from it and put it in a variable and you do not want to print a Null value, then you will perform this method to check and investigate the variable:

<!DOCTYPE html>
<html>
<body>

<h2>Testing Null Values</h2>

<span id="mySpan"></span>

<script>
var ID = 46584;
if(! ID)
{
document.getElementById("mySpan").innerHTML = "Unfortunately but there is no data to show this time!";
}
else{
  document.getElementById("mySpan").innerHTML = "Your ID is: " +ID;
}

</script>

</body>
</html>

Did you see what I did in the previous code? , I put a random value in a JavaScript variable and wanted to check its value in js if boolean using Javascript operators, then I protected this value so that it would not appear in front of the visitor in the form of Undefined value by placing it in two correct possibilities. Then I called the HTML tags and modified the value of the Span tag to be Show the result in a coordinated and beautiful way.

And you, too, always protect your codes while showing them to the visitor, because the visitor of your site does not like to see program values ​​appear to him, even if he does not know that, but he does not like to enter a site with pages that are not fully equipped.

This article was an important part in the world of programming and I hope that you have benefited even a little. Put this page in your favorites list and publish it to all your friends in order to add important topics that will impress you in the world of programming.

 

Tips

  • js if boolean is used a lot in advanced projects.
  • Boolean variables are important in databases and game programming.
  • In order to understand the Boolean variables well, save and apply the codes in your browser and see the results.
  • The task of Boolean variables is to control the code in a professional manner that you do not master in the language of numbers and texts.
  • You can check any variable using Boolean method to check whether it has a value or not.

 

References

  •  Partially referenced with Third Edition JavaScript Book.

 

Leave a comment

Your email address will not be published. Required fields are marked *