title: How to set preftix and delete after character in each line in txt file with c#
body: <p>Hello i'm getting some strings from a Web API 
  <a href="https://api.hackertarget.com/hostsearch/?q=google.com" rel="nofollow noreferrer">Like This</a></p>
  
  <pre><code>mail-lf0-f100.google.com,209.85.215.100
  mail-vk0-f100.google.com,209.85.213.100
  mail-ua1-f100.google.com,209.85.222.100
  mail-ed1-f100.google.com,209.85.208.100
  mail-lf1-f100.google.com,209.85.167.100
  mail-ej1-f100.google.com,209.85.218.100
  mail-pj1-f100.google.com,209.85.216.100
  mail-wm1-f100.google.com,209.85.128.100
  mail-io1-f100.google.com,209.85.166.100
  mail-wr1-f100.google.com,209.85.221.100
  mail-vs1-f100.google.com,209.85.217.100
  mail-ot1-f100.google.com,209.85.210.100
  mail-qv1-f100.google.com,209.85.219.100
  mail-yw1-f100.google.com,209.85.161.100
  </code></pre>
  
  <p>it give me some string records and i want to do this <strong>Operations</strong>.</p>
  
  <ol>
  <li><p>I want to make it line by line like it show in original</p></li>
  <li><p>I want to remove everything after comma in eachline </p></li>
  <li><p>I want to set a prefix before each line for the example:</p></li>
  </ol>
  
  <p><strong>Example:</strong> <code>Google.com to&gt;&gt;      This is Dns: Google.com</code></p>
  
  <p>and This is my code . What should i edit and what should i add?</p>
  
  <pre><code>        string filePath = "D:\\google.txt";
          WebClient wc = new WebClient();
          string html = wc.DownloadString("https://api.hackertarget.com/hostsearch/?q=Google.com");
          File.CreateText(filePath).Close();
          string number = html.Split(',')[0].Trim();
          File.WriteAllText(filePath, number);
          MessageBox.Show("Finish");
  </code></pre>