Javascript Type of Operator

Rate this post

The typeof operator is a unary operator that is placed before its single operand, which can be of any type. Its value is a string indicating the data type of the operand.

The typeof operator evaluates to “number”, “string”, or “boolean” if its operand is a number, string, or boolean value and returns true or false based on the evaluation.

Here is a list of the return values for the typeof Operator.

Type String Returned by typeof
Number “number”
String “string”
Boolean “boolean”
Object “object”
Function “function”
Undefined “undefined”
Null “object”


The following code shows how to implement typeof operator.

      <script type="text/javascript">
            var a = 10;
            var b = "String";
            var linebreak = "<br />";
            result = (typeof b == "string" ? "B is String" : "B is Numeric");
            document.write("Result => ");
            result = (typeof a == "string" ? "A is String" : "A is Numeric");
            document.write("Result => ");
      <p>Set the variables to different values and different operators and then try...</p>


Result => B is String 
Result => A is Numeric
Set the variables to different values and different operators and then try...

Related Posts

  • 56
    We will discuss two operators here that are quite useful in JavaScript: theconditional operator (? :) and the typeof operator. Conditional Operator (? :) The conditional operator first evaluates an expression for a true or false value and then executes one of the two given statements depending upon the result…
    Tags: operator, var, result, values, javascript
  • 54
    JavaScript Datatype One of the most fundamental characteristics of a programming language is the set of data types it supports. These are the type of values that can be represented and manipulated in a programming language. JavaScript allows you to work with three primitive data types − Numbers, 123, 120.50…
    Tags: javascript, var, type, values
  • 47
    Let us take a simple expression 4 + 5 is equal to 9. Here 4 and 5 are calledoperands and ‘+’ is called the operator. JavaScript supports the following types of operators. Arithmetic Operators Comparision Operators Logical (or Relational) Operators Assignment Operators Conditional (or ternary) Operators Lets have a look…
    Tags: result, var, javascript, operator
  • 40
    Variables are nothing but reserved memory locations to store values. This means that when you create a variable you reserve some space in memory. Based on the data type of a variable, the interpreter allocates memory and decides what can be stored in the reserved memory. Therefore, by assigning different…
    Tags: values, string, operator, type
  • 37
    JavaScript supports the following logical operators − Assume variable A holds 10 and variable B holds 20, then − Sr.No Operator and Description 1 && (Logical AND) If both the operands are non-zero, then the condition becomes true. Ex: (A && B) is true. 2 || (Logical OR) If any…
    Tags: result, operand, operator, var, values, javascript, boolean

Leave a Reply

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

%d bloggers like this: