title: How can I get From a SSRS DataSet Row the Value Where Condition is True
body: <p>I have a DataSet called Reporting that include TagName, Value and DateTime.</p>
  
  <p>Now my question: In my SSRS Report I have a TextBox where I want the Value of a TagName.</p>
  
  <p>For Example: I have TagName called: <code>"TT101"</code> with the Value <code>21</code>.</p>
  
  <p>So my TextBox should show <code>21</code>.</p>
  
  <p>I have tried with this expression:</p>
  
  <pre><code>=IIf(Fields!TagName.Value = "TT101" , Fields!Value.Value ,0)
  </code></pre>
  
  <p>So I expected the output this expression to be <code>21</code> but it was <code>0</code> because it's always <code>false</code> or <code>Null</code> and I can't find out why?</p>