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Understanding Commands in WPF: A Cleaner Alternative to Button Click Events

Many WPF developers start by using Button Click events for handling user actions. At first, this seems simple and straightforward. But very soon, the code-behind file becomes huge , and maintaining it turns into a challenge. One big problem arises: when the logic changes, the button does not enable or disable automatically , and testing button click logic becomes very difficult. So the big question is: Is there a better way to handle button actions in WPF? The answer is Commands . In this post, we’ll learn how to use Commands in WPF with a simple, practical example. We’ll cover: What a Command is How it works Why using Commands is better than Click events How buttons can automatically enable or disable based on conditions What is a Command in WPF? In WPF, a Command acts as a middle layer between the UI and your logic. Instead of the button directly calling a method, it triggers a Command , and the Command decides: What code should run Whether the button s...

Leetcode - 125. Valid Palindrome

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 Problem statement: A phrase is a   palindrome   if, after converting all uppercase letters into lowercase letters and removing all non-alphanumeric characters, it reads the same forward and backward. Alphanumeric characters include letters and numbers. Given a string  s , return  true   if it is a  palindrome , or  false  otherwise . Solution: Problem says, First convert all  uppercase letters into lowercase letters. Remove all non-alphanumeric characters. For first part, I will use ToLower() method of string class. this method will convert all the  uppercase letters into lowercase letters. For the second part, I will use Regex Replace method to remove all  non-alphanumeric characters.  public bool IsPalindrome(string s)   {         /*here i am checking if string is null or empty if so then it will be always                   ...