title: sharepoint filter DataFormWebPart within TextBox
body: <p>I want to filter DFWP through asp:TextBox.</p>
  
  <p>Using Office Designer I added DFWP with data to the page. 
  Added asp:textbox with runat server, autopostback and ID="textBoxSearch".
  Created variable [var] in DFWP and in the source section chose element textBoxSearch.</p>
  
  <p>Then added filter "field_1 contains [var]". </p>
  
  <p>This search(filter) worked greatly for two weeks, then filter broken. Only recreating DFWP helped. After another week filter was broken. Any text in textbox was  ignored by filter.</p>
  
  <p>I figured out that SP can't see asp:textbox "textBoxSearch" in variable [var], because if change "contains [var]" to "contains 'some text'" it will work.</p>
  
  <p>How can it be - working some time, then accidentally not?</p>
  
  <p>If not using internal filter web-part, but textbox, how to fix it?</p>