title: Format json String and pass it to the body with parameters gives error
body: <p>I am trying to create a post request using RestSharp.</p>
  
  <p>I have the following string </p>
  
  <pre><code>"{ \"name\": \"string\", \"type\": \"string\", \"parentId\": \"string\", \"Location\": [ \"string\" ]}"
  </code></pre>
  
  <p>I need to pass that into the json body to send a POST request I am trying the following.</p>
  
  <pre><code>public IRestResponse PostNewLocation(string Name, string Type, Nullable&lt;Guid&gt; ParentId, string Locatations)
  {
    string NewLocation = string.Format("{ \"name\": \"{0}\", \"type\": \"{1}\", \"parentId\": \"{2}\", \"Location\": [ \"{3}\" ]}", Name, Type, ParentId, Location);
    var request = new RestRequest(Method.POST);
    request.Resource = string.Format("/Sample/Url");
    request.AddParameter("application/json", NewLocation, ParameterType.RequestBody);
    IRestResponse response = Client.Execute(request);
  }
  </code></pre>
  
  <p>And the error</p>
  
  <pre><code>Message: System.FormatException : Input string was not in a correct format.
  </code></pre>
  
  <p>How can I format the above string to pass it into the json body?</p>
  
  <p>My Test fails at this line </p>
  
  <pre><code>string NewLocation = string.Format("{ \"name\": \"{0}\", \"type\": \"{1}\", \"parentId\": \"{2}\", \"Location\": [ \"{3}\" ]}", Name, Type, ParentId, Location);
  </code></pre>