To get a string contains only numbers (0-9) we use a regular expression (/^ +$/) which allows only numbers. JavaScript Program to Make a Simple Calculator In this example, you will learn to write a program to make a simple calculator in JavaScript. For now, we stick to the minimum viable functionalities for our basic calculator. However before understanding each function, first you need to setup your html page. The reason is simple: long, long time ago JavaScript was a much weaker language, many things could only be done with eval. The display() function will display the selected number on the calculator screen. Just copy paste the below script in to an html file and run on any browser to see the working.
I remember doing a JavaScript calculator project about 5 months ago but it was clear today that that I must have just copied the solution as a code along as Brian Holt typed through it. External CSS: A separate CSS file with the style attributes linked with the main file in the root directory.Next, the match () method of the string object is used to match the said regular expression against the input value. As per the bedmas rule, order of operations is '+' then '-' (left to right) Hence, 25 + 327 Contribute to rhprabhu/javascript-calculator-without-eval development by creating an account on GitHub. In this article, we will create a calculator step-by-step. js should still work on older browsers when using the es5-shim. This online trigonometry calculator will calculate the sine, cosine, tangent, cotangent, secant and cosecant of angle values entered in degrees or radians. Calorie calculator gives suggestion about daily needs of fat, protein, carbohydrate. First off all we have created one table and we create 10 Button 0 to 9.