Checking for division by zero

Question

Checking for division by zero

I have a question about my calculator. I want to ensure that if the input string contains "0", an error alert is displayed. However, I do not want to check for the "/" character. Below is the function I have written:

<input type="text"  name="answer" id="t" onkeyup="isAllowedSymbol(this);checkLength(this);" placeholder="Enter data" >

<input type="button" value=" &#247; " onclick="calculator.answer.value += '/';div(this);checkLength(this);" />

    function div(input) 
{
    var input = document.getElementById("t");
    var lastElement = (input.value.length-1);
    //alert(input.value.charAt(lastElement));
    if (input.value.charAt(lastElement) == 'null')
        { 
            alert(" / to Zero");
        }
}

javascript html css

Answer 1

Answer №1

To assess the numerical value of a string, one can utilize the parseInt function.

if (parseInt($("#myInput").val()) > 0) {
  // Carry out a specific action...
}

Furthermore, one can identify division by zero by employing the isFinite method:

if (isFinite(1/0)) {
   // This section will not be executed
} else {
   ...
}

The isFinite function will also yield false for NaN:

if (isFinite(NaN)) {
   // This part will not be executed
} else {
   ...
}

Answer 2

To assess the numerical value of a string, one can utilize the parseInt function.

if (parseInt($("#myInput").val()) > 0) {
  // Carry out a specific action...
}

Furthermore, one can identify division by zero by employing the isFinite method:

if (isFinite(1/0)) {
   // This section will not be executed
} else {
   ...
}

The isFinite function will also yield false for NaN:

if (isFinite(NaN)) {
   // This part will not be executed
} else {
   ...
}

Answer 3

Answer №2

Stop using

input.value.charAt(lastElement) == 'null'

when creating your if statement, consider using

input.value[lastElement-1]+input.value[lastElement] === "/0"

This will verify if the final part of the string is zero immediately following the / symbol.

function div(input) 
{
    var input = document.getElementById("t");
    var lastElement = (input.value.length-1);
    if (input.value[lastElement-1]+input.value[lastElement] === "/0")
        { 
            alert(" / to Zero");
        }
}

<input type="text"  name="answer" id="t" placeholder="Enter data" >

<input type="button" value=" &#247; " onclick="div(this);" />

Answer 4

Stop using

input.value.charAt(lastElement) == 'null'

when creating your if statement, consider using

input.value[lastElement-1]+input.value[lastElement] === "/0"

This will verify if the final part of the string is zero immediately following the / symbol.

function div(input) 
{
    var input = document.getElementById("t");
    var lastElement = (input.value.length-1);
    if (input.value[lastElement-1]+input.value[lastElement] === "/0")
        { 
            alert(" / to Zero");
        }
}

<input type="text"  name="answer" id="t" placeholder="Enter data" >

<input type="button" value=" &#247; " onclick="div(this);" />

Answer 5

Answer №3

While this may not provide a comprehensive solution, what are your thoughts on this snippet of code?

function checkDivision(input) 
{
    var input = document.getElementById("t");
    var lastCharIndex = (input.value.length - 1);

    // Uncomment to display specific characters in input
    // alert(input.value[lastCharIndex - 1]);
    // alert(input.value[lastCharIndex]);

    if (input.value[lastCharIndex - 1] === "/") 
    { 
        if (input.value[lastCharIndex] === "0") 
        { 
            alert(" / followed by Zero");
        }
    }
}

Answer 6

While this may not provide a comprehensive solution, what are your thoughts on this snippet of code?

function checkDivision(input) 
{
    var input = document.getElementById("t");
    var lastCharIndex = (input.value.length - 1);

    // Uncomment to display specific characters in input
    // alert(input.value[lastCharIndex - 1]);
    // alert(input.value[lastCharIndex]);

    if (input.value[lastCharIndex - 1] === "/") 
    { 
        if (input.value[lastCharIndex] === "0") 
        { 
            alert(" / followed by Zero");
        }
    }
}

Checking for division by zero

Answer №1

Answer №2

Answer №3

Similar questions

How can JavaScript transform Unicode strings?

Tips for Preventing Page Scrolling When Clicking on a Hashed A Tag in Content with a Fixed

Having trouble with creating SQLite tables using JavaScript within a for loop

Launching event handlers and applying CSS classes within a single scenario

Scraping data from a support portal using JSOUP

JavaScript's setTimeout function seems to be executing an excessive number of times

Axios is causing my Pokemon state elements to render in a jumbled order

How can I properly initialize React components?

Connecting to particular sections on other pages

Intercepting HTTP requests on specific routes with Angular 4+ using an HTTP Interceptor

transition effect of appearing and disappearing div

How can I insert PHP code within the style attribute of a div tag?

Breaking down a lengthy series of items into several smaller lists

Switching PHP include on an HTML page using JavaScript

Retrieve the CSS selector for the element that my plugin has been implemented on

Upon removing an element, the button click event fails to trigger

Deleting database information using Jquery when a div is clicked

What is the best way to retrieve a comprehensive outcome from a sql search utilizing php and consequently showcase it using javascript?

Encountered difficulties while attempting to use keyboard input and received a null value when attempting to retrieve a data-* attribute using Python and Selenium

Troubleshooting Issue with Query Functionality in MEAN App's Find Request