title: C# Stringbuilder replace with a null value
body: <p>Im trying to use Stringbuilder to build me a csv file and some of the fields from the files I'm using have double quotes in. 
  I have this code as you can see I am trying to use the .replace to remove the <code>"</code> and replace with <code>nothing</code>, this throws an empty char literal error. Is there an easier way of removing all double quotes  `</p>
  
  <pre><code>public void Manipulatefile(string csv, string suffix)
      {
          StringBuilder formattedData = new StringBuilder();
  
          // Read all file lines into a string array.
          string path = @csv;
          string[] fileLines = File.ReadAllLines(path);
  
          foreach (string fileLine in fileLines)
          {
  
              string[] lineItems = fileLine.Split(new char[1] { ',' });
  
  
              string forename = lineItems[0];
  
  
              string surname = lineItems[1];
  
  
              formattedData.Append(forename);
  
              // Add the CSV seperator.
              formattedData.Append(",");
  
              // Append the forename to the current CSV output line.
              formattedData.Append(surname);
  
  
              formattedData.Append(",");
  
              formattedData.Append(forename.Substring(1,1));
              formattedData.Append(surname);
              formattedData.Append(suffix);
  
              formattedData.Replace('"', '');
              formattedData.AppendLine();
  
              File.WriteAllText(@"C:\test\MyFile.csv", formattedData.ToString());
          }
  </code></pre>
  
  <p>Thanks </p>