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JavaScript: Get the data type

JavaScript Function: Exercise-9 with Solution

Write a JavaScript function which accepts an argument and returns the type.

Note : There are six possible values that typeof returns: object, boolean, function, number, string, and undefined.

Sample Solution: -

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Detect JavaScript Data Types</title>
</head>
<body>
  
</body>
</html>

JavaScript Code:

function detect_data_type(value)
{
var dtypes = [Function, RegExp, Number, String, Boolean, Object], x, len;
    
if (typeof value === "object" || typeof value === "function") 
    {
     for (x = 0, len = dtypes.length; x < len; x++) 
     {
            if (value instanceof dtypes[x])
            {
                return dtypes[x];
            }
      }
    }
    
    return typeof value;
}
console.log(detect_data_type(12));
console.log(detect_data_type('w3resource'));
console.log(detect_data_type(false));

Sample Output:

number
string
boolean

Flowchart:

Flowchart: JavaScript function: Get the data type

Live Demo:

See the Pen JavaScript -Check a number is prime or not-function-ex- 8 by w3resource (@w3resource) on CodePen.


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JavaScript: Tips of the Day

Empty a JavaScript Array

To empty a JavaScript array, we can set its length property to 0.
For instance. we can write:

const arr = ['a', 'b', 'c'];
arr.length = 0;

Then arr would be an array with no length.
Likewise, we can just assign it an empty array:

const arr = ['a', 'b', 'c'];
arr.length = [];

Ref: https://bit.ly/2LBj213