Error - NotImplementedException Was Unhandled

Question

I'm trying to subtract the result of 2 variables and I want to echo the result in Selenium.

I'm using VS2015 as my IDE.

//Obtaining pressure For 2100 hours today
driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[16]")).Click();
    
//Obtain pressure for 2200 Hours tomorrow
driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[7]")).Click();
    
//Subtract the two values above and then 'echo' the result in Selenium
int var2 = 1014;
    
var2 - var1 = 

The last part of the code is where I require some assistance, please.

Any ideas?

Here is the code:

using System;
using System.Collections.Generic;
using System.Linq;
using NUnit.Framework;
using OpenQA.Selenium;
using OpenQA.Selenium.Firefox;
using System.Text;
using System.Threading.Tasks;
using OpenQA.Selenium.Support.UI;

namespace BBC_W_FCast_New_01
{
    class Program
    {
        static void Main(string[] args)
        {
            //Instantiate Firefox Driver
            var driver = new FirefoxDriver();
            driver.Navigate().GoToUrl("http://www.bbc.co.uk/weather");

            //Using the 'Find a Forecast' search field to get the weather in 'Reading, UK'
            var user = driver.FindElement(By.Id("locator-form-search"));

            //Use "Reading, Reading" to avoid ambiguity. There is a location called Reading in USA
            user.SendKeys("Reading, Reading");

            //Click on Search button
            driver.FindElement(By.Id("locator-form-submit")).Click();

            //WebDriver Wait
            //Trial Code 1 - WebDriverWait wait = new WebDriverWait(driver, 30);
            //Trial Code 2 - wait.until(ExpectedConditions.visibilityOfElementLocated(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[10]")));

            WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromSeconds(10));
            IWebElement element = wait.Until(ExpectedConditions.ElementToBeClickable(By.Id("detail-table-view")));

            //Click on Table button
            driver.FindElement(By.Id("detail-table-view")).Click();

            //Obtaining pressure For 2100 hours today
            driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[10]")).Click();
                                                     
            //Obtain pressure for 2100 Hours tomorrow
            driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[16]")).Click();

            //Subtract the two values above and then 'echo' the result in Selenium
            int val1 = Int32.Parse(driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[16]")).Text);
            int val2 = Int32.Parse(driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[10]")).Text);

            int difference = val1 - val2;
System.Console.WriteLine("Difference is: " + difference);
        }
    }

    internal class WebDriverWait
    {
        private FirefoxDriver driver;
        private TimeSpan timeSpan;

        public WebDriverWait(FirefoxDriver driver, TimeSpan timeSpan)
        {
            this.driver = driver;
            this.timeSpan = timeSpan;
        }

        internal IWebElement Until(object p)
        {
            throw new NotImplementedException();[![Error - NotImplementedException Was Unhandled][1]][1]

Screenshot of error:

Answer 1

The first two driver.FindElement just click on the cells; probably you would want to query their content as well:

`var cell16 = driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[16]")).Text();`

After that, you would make the subtraction:

var result = cell16 + cell07;

Console.WriteLine(result);