JavaScript to find the position of the left most vowel in the string

This program includes Javascript to find the position of the left most vowel in a string. This javascript is quite simple. We run a loop until the length of the input string is reached. Inside the loop, we go through each character of the string and check if a vowel (a, e, i, o, u) is present.

Input Parameter: A string
Output: Left-most vowel and the position of the left most vowel in the string

//FindLeftmostVowel.html
<!DOCTYPE HTML>
<?xml version="1.0" encoding="UTF-8"?>
<html>
<head>
<script type ="text/javascript">
function str_vowel()
{
var str=prompt("Enter the string\n", " ");
for(var i = 0; i<str.length; i++)
{
if (str.charAt(i) =='a' || str.charAt(i) == 'e' || str.charAt(i) =='i'
|| str.charAt(i) == 'o' || str.charAt(i) == 'u' || str.charAt(i) == 'A' ||
str.charAt(i) == 'E' || str.charAt(i) =='I' || str.charAt(i) =='O' || str.charAt(i) == 'U')
{
document.write("The entered string is:" +str+ "<br/>");
document.write("The leftmost vowel is :"+str.charAt(i)+"<br/>");
var pos = i+1;
document.write("The position of the leftmost vowel " +str.charAt(i)+ " is:" +pos+"\n");
exit;
}
}
document.write("The entered string is:" +str+ "<br/>");
document.write("The entered string has no vowels");
}
</script>
</head>
<body style="background-color:green" onload = "str_vowel();"> <!-- Not recommended to use insline styeling -->
</body>
</html><br>

//FindLeftmostVowel.html

<!DOCTYPE HTML>

<?xml version="1.0" encoding="UTF-8"?>

<html>

<head>

function str_vowel()

{

var str=prompt("Enter the string\n", " ");

for(var i = 0; i<str.length; i++)

{

if (str.charAt(i) =='a' || str.charAt(i) == 'e' || str.charAt(i) =='i'

|| str.charAt(i) == 'o' || str.charAt(i) == 'u' || str.charAt(i) == 'A' ||

str.charAt(i) == 'E' || str.charAt(i) =='I' || str.charAt(i) =='O' || str.charAt(i) == 'U')

{

document.write("The entered string is:" +str+ "<br/>");

document.write("The leftmost vowel is :"+str.charAt(i)+"<br/>");

var pos = i+1;

document.write("The position of the leftmost vowel " +str.charAt(i)+ " is:" +pos+"\n");

exit;

}

document.write("The entered string is:" +str+ "<br/>");

document.write("The entered string has no vowels");

}

</script>

</head>

</body>

</html><br>

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Go through the following video to understand how to run this javascript:

Input:

Output 1: Success case

Output of the left most vowel in a given string using javascript

diagram showing the left most vowel in the given string using javascript

Output 2: When the input string contains a white space

Output of the left most vowel in the given string with space using javascript

Diagram shows the left most vowel in a string when there is a white space

Output 3: When there is no vowel present

How to execute this script?

Copy the code to a text file and save it with a .html extension.
Open this file in a browser.
You will be asked to enter a string and result will be displayed.
To check for another string, refresh the web page and enter a new string. You can refer to the video for easy understanding.

Please let me know if you encounter any problems.

JavaScript to find the position of the left most vowel in a string

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