title: how to create a textbox in ssrs for user entry as a parameter
body: <p>I have a report that has three params. one is dropdown. It created automatically when i supplied 
  name and value, Then If we select multivalue, it shows multivalue dropdownlist.</p>
  
  <p>But I am not able to create a textbox. That will act as a parameter to be supplied in report.</p>
  
  <p>for that I have created a parameter, set it to allow null and datatype = "text" . 
  parameter visibility is also visible but as a result I can see a textbox which is a disbled one. </p>
  
  <p>How can this textbox be made to work?</p>