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POObject reference not set to an instance of an object - but it is?
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  1. POObject reference not set to an instance of an object - but it is?
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    copied!<p>I am creating a Sudoku Puzzle in asp and I'm having trouble with some classes. When I create a function to display all the numbers in the text box, I get this error: Object reference not set to an instance of an object. I know that it means that my object is null, but here is my code. The line that I am getting the error on is the line that says: stbNumber.setNumber(currentSolution[3 * i + m, 3 * k + n]);</p> <pre><code>private SudokuTextBox stb; private Puzzle puzzle; private Box box; private Number stbNumber; public void displayAll(object sender,EventArgs e) { puzzle = new Puzzle(); for (int i = 0; i &lt; 3; i++) { for (int k = 0; k &lt; 3; k++) { box = new Box(); for (int m = 0; m &lt; 3; m++) { for (int n = 0; n &lt; 3; n++) { stbNumber = new Number(); stb = new SudokuTextBox(); stbNumber.setNumber(currentSolution[3 * i + m, 3 * k + n]); stb.setTextBoxValue(stbNumber); stb.setVisibility(true); box.setItem(stb, m, n); }// end forth for }//end third for puzzle.setItem(box, i, k); }//end second for }//end first for generateBoxes(); } </code></pre> <p>I have initialized stbNumber at the very top of my code, and I have made sure that currentSolution is not null or empty. I'm therefore unsure as to what I am doing wrong. I also should mention that I have this exact code elsewhere to generate new puzzles and it works just fine, but this section of code specifically gets called when I click a button.</p>
 

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