Tag Archives: express

How to create JavaScript Regular Expressions for the validation of International telephone numbers with extensions [on hold]

Questions: I’m trying to match international phone numbers with extensions such as: +44 (123) 123 4567 ext. 123 and telephone numbers such as: +44 (123) 123 4567. When I type the extension it returns an invalid phone number. I also want to match US telephone numbers such as (212) 555-1212 and other telephone numbers, for… Read More »

How to create first Windows Forms DevExpress application

Questions: I am new to using DevExpress.the process of creating a WinForm using DevExpress isn’t clear to me Yet. I tried reading the DevExpress documentation but it seems more difficult than using WinForms just confused me more. I found myself using only WinForms to create my User interfaces without using DEVExpress. So please can you… Read More »

React-Native: JavaScript regular expression exception (Invalid group) on release mode

Questions: I wrote following function in order to parse available image sizes inside srcset attribute for each img element and return it as array. Everything works as expected when the debug mode is on, but once I disable the debug mode, the app would crash and throw following error: Error: invalid regular expression invalid group… Read More »

Validating the mathematical or arithmetic expression from a input string in JavaScript

Questions: I need a solution for validating a mathematical or arithmetic expression from a form input using JavaScript or TypeScript. The validator should allow arithmetic operator like (), +, -, *, /, avg(), min(), max(). I am looking for a validator, not the math evaluator. For example, the input can be ((x+y-z)+(min(min(x,y),z)+avg(x,y)). Answers: