title: How to extract value betwen two string using regex?
body: <p>Here is the demo String:</p>
  
  <blockquote>
    <p>beforeValueAfter</p>
  </blockquote>
  
  <p>Assume that I know the value I want is between "before" and "After"
  I want to extact the "Value" using the regex....</p>
  
  <blockquote>
    <p>pervious909078375639355544after</p>
  </blockquote>
  
  <p>Assume that I know the value I want is between "pervious90907" and "55544after"
  I want to extact the "83756393" using the regex....</p>
  
  <p>thx in advance.</p>