title: C#: Pointer to double
body: <p>I have a declaration and in the declaration, I want to set a height is a pointer to a double but get the error mesasage: </p>
  
  <blockquote>
    <p>Error 1 Pointers and fixed size buffers may only be used in an unsafe
    context,</p>
  </blockquote>
  
  <p>Can someone show me the right way to declare the type of pointer in a double ?</p>
  
  <p>Below is mine declaration and I set the height to a pointer of double <code>(double* height)</code> but gets an error message.</p>
  
  <pre><code>private static extern bool GetElevation(double dLat, double dLon, double* height);
  </code></pre>