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PObutton array NullReferenceException was unhandled
 

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    <p>First of all i'm new in here and new with csharp. just exhausted while doing some exercises for learning csharp. cant find a solution why i get the error "NullReferenceException was unhandled" and </p> <p>1) How to overcome this? according to my researches its related with initialisation but couldnt make it. i debug and watched the values all buttons gets gets null values is it because of this? how can i solve it? what to do? which code to add? </p> <p>(***all informing knowledge about class initialisations and arrays and null stuffs are welcome. i wanna learn all the points and wanna be expert :P and people can optimize the code as well. all extra informations are welcome.)</p> <p>2) And why compiler doesnt show error but error comes while running the code?</p> <p>ok now i have the code blow</p> <pre><code>using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace temp1 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { Button[] btn = new Button[5]; for (int i = 0; i &lt; 5; i++) { btn[i] = new Button(); btn[i].Width = 50; btn[i].Height = 50; flowLayoutPanel1.Controls.Add(btn[i]); btn[i].Click += new EventHandler(btn_Click); } } void btn_Click(object sender, EventArgs e) { Button[] btn = sender as Button[]; btn[3].Text = "button name changed"; // here problems occurs //btn[3].BackColor = Color.Red; // here problems occurs // btn[3].PerformClick(); // here problems occurs } } } </code></pre>
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