Increment a double value
<p>I'm using this part of code in my system.</p>

<pre><code>double countA = 0.00;  
double countB = 0.00; 


if (myrow.grade == "A") 
{ 
  countA += 1.00; 
}
else if (myrow.grade == "B") 
{
  countB += 1.00;  
}

countALabel.Text = Convert.ToString(countA);
countBLabel.Text = Convert.ToString(countB);
</code></pre>

<p>The code is supposed to calculate how many student in my <em>examMarks</em> table that get "A" or "B" and display it using labels. However I keep getting <code>0</code> value even if there are students who get "A" and "B" in my table?</p>

<p>How do i get the increment value?</p>
