title: How to find out if string has already been URL encoded?
body: <p>How could I check if string has already been encoded? </p>
  
  <p>For example, if I encode <code>TEST==</code>, I get <code>TEST%3D%3D</code>. If I again encode last string, I get <code>TEST%253D%253D</code>, I would have to know before doing that if it is already encoded...</p>
  
  <p>I have encoded parameters saved, and I need to search for them. I don't know for input parameters, what will they be - encoded or not, so I have to know if I have to encode or decode them before search.</p>