title: How to join together some strings with conditions?
body: <p>I have the next code:</p>
  
  <pre><code>string result = string.Join(",", 
  someCondition1 ? str1 : string.Empty,
  someCondition2 ? str2 : string.Empty,
  someCondition3 ? str3 : string.Empty,
  //some other conditions like those
  ......
  );
  </code></pre>
  
  <p>If I have:</p>
  
  <pre><code>someCondition1 = true; str1 = "aaa";
  someCondition2 = false; str2 = "bbb";
  someCondition3 = true; str3 = "ccc";
  </code></pre>
  
  <p>Then result looks like "aaa,,ccc" but I need "aaa, ccc" (there is NO empty string).
  Which is the best way to do this?</p>