How to pass a dymamic variable inside a method in javascript?

javascript dynamic variable name in loop
javascript dynamic variable name in object
javascript create variable name from string
jquery dynamic variable name
javascript dynamic object property name
dynamic variable names python
react dynamic variable name
dynamic variable name java

I am building a function to reverse a string but for unknown reasons to me and since I am very new to javascript (3 days only) I can not figure it out or it is possible that I have not grasped one or two concepts with the language.

Basically, I determine the length of the string which I use for the loop. After that, I try to use the same loop variable in the slice method to run thru the string from the right to left, 1 character at a time.

So far, I know that the loop is working just fine but I get no values from phrase.slice(i,1) but if I substitute i by a real number it works.

I think that I have a conceptual problem here and dynamic variables cannot be assigned to methods. I know this can be achieved using other methods but I would like to know why is this failing when it makes all the sense to me.

function reverseWords(phrase) {

  var build_reverse_word;

  for (let i = phrase.length ; i > 0 ; i--) {

    console.log(i); //This is just to verify that my loop is working

    build_reverse_word = phrase.slice(i,1);

    build_reverse_word = build_reverse_word + build_reverse_word;
  }

  return build_reverse_word;
}

let reverse_word_result = reverseWords("Dogs are Great Animals");

console.log(reverse_word_result);

What I am trying to achieve is to reverse the string backward. Thank you for your support.

The .slice method takes in 2 arguments. begin and end. You want to extract just one letter on every iteration. But in your case the passed in arguments are not proper.

function reverseWords(phrase) {

  let build_reverse_word = '';

  for (let i = phrase.length; i > 0; i--) {

    let extracted_letter = phrase.slice(i - 1, i);

    build_reverse_word = build_reverse_word + extracted_letter;
  }
  return build_reverse_word;
}

let reverse_word_result = reverseWords("Dogs are Great Animals");

console.log(reverse_word_result);

How do I create dynamic variable names inside a loop?, However, this can also be accomplished in JavaScript by simply adding properties You can use eval() method to declare dynamic variables. This method uses the ‘onclick’ property of ‘a’ tag, i.e, whenever the link (‘a’ tag) is clicked, an ‘onclick’ event is triggered. Here we will use this onclick event to generate a new URL and redirect the user to that URL. (NOTE: This URL will contain the Variable we want to use

your problem is that you are using the slice() method. The slice method is defined as such list.slice(startIndex,endIndex). Since, your code makes it such that the endIndex is always 1, JS is trying to find a word which starts at a high number, say 21 to a low number 1 which will never work. All slices must have an endIndex > startIndex. Thus, your code should look like this.

function reverseWords(phrase) {

     var build_reverse_word;

     for (let i = phrase.length ; i > 0 ; i--) {

        console.log(i); //This is just to verify that my loop is working

        build_reverse_word = phrase.slice(i-1,i);
        console.log(build_reverse_word)
        build_reverse_word = build_reverse_word + build_reverse_word;
     }
return build_reverse_word;
}

let reverse_word_result = reverseWords("Dogs are Great Animals");

console.log(reverse_word_result);   

${"dynamic" + $i} variable names in javascript - JavaScript, However I can't work out how to create a dynamic variable name in javascript. I agree that arrays and objects are simpler. I basically need to pass these variables into an ajax GET request so I can use them in the requested php script. Global Variables: Global variable is a variable which is declared outside of any function and is accisible to all the methods across the program, meaning that it is variable with global scope. The set of all global variables are usually declared on the top of all the functions.

Sushanth gave you the solution to your problem! But since you're also learning the language I would like to give you a few principles on strings:

A string is an instance of the parent object String and one of the six primitives. The characters in the strings can be accessed by the bracket notation [] or with the method charAt.

That means that charAt or the bracket notation would've worked too and probably less confusing than using slice.

const stringValue = "Dogs are Great Animals"; //make it a constant (it will not change)

//a string is a instance of the super String, which has methods to it like slice and toUppercase.

console.log(stringValue[1]); //get the letter at position 1 - remember JavaScript is zero based.

//use a countdown (more memory efficient and less complicated
let reversed = "";
for (let i = stringValue.length-1; i >= 0; i--)
{
  reversed += stringValue[i];//use the += as a shorthand for reversed = reversed + ...
}
console.log(reversed);

How to use dynamic variable names in JavaScript ?, Inside eval(), we pass a string in which variable valuei is declared and assigned a value of i for each iteration. The eval() function executes this and creates the  Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. Learn more Is it Possible to pass a variable inside a function as parameter in javascript?

The Dollar Sign ($) and Underscore (_) in JavaScript, named marker (undefined); then add to i; then try to assign a value to to the result of an expression, not possible. One more thing: If you are using a variable to construct an regexp, cares should be taken that the variable might contain regexp special characters. e.g. if you pass "c++", the regex compiler will complain SyntaxError: Invalid regular expression: /c++/: Nothing to repeat – dotslashlu Dec 19 '16 at 3:37

JavaScript Basics: String Concatenation with Variables and , code represented as a string in the parameter. A string is passed as a parameter to eval(). If the string represents an expression, eval() evaluates the expression. A JavaScript closure is required to pass extra data to a callback or exception handler prior to the 3.0 release. For example, your callback method needs to look something like this: For example, your callback method needs to look something like this:

How do I create dynamic variable names inside a JavaScript loop?, identifiers, which just means that they identify an object in the same way a name would. The objects they identify include things such as variables, functions, properties, events, and objects. The task is to pass a string as a parameter on onClick function using javascript, we’re going to discuss few techniques. Example 1: This example simply put the argument which is string in the onClick attribute of the button which calls a function with a string as an argument using onClick() method .