title: C++ Invalid use Of Member Function (Did You Forget The '()'?)
body: <p>I'm having trouble getting my program to compile. The error is happening on line 165-177. All I added was the test for the presence of letters and I got an error, hope you can help!
  Full Code <a href="http://pastebin.com/embed.php?i=WHrSasYk" rel="nofollow noreferrer">http://pastebin.com/embed.php?i=WHrSasYk</a></p>
  
  <p>(Attached below is code)</p>
  
  <pre><code>do
  {
    cout &lt;&lt; "\nCustomer Details:";
  
    cout &lt;&lt; "\n\tCustomer Name:";
    cout &lt;&lt; "\n\t\tFirst Name:";
    getline (cin, Cust_FName, '\n');
    if (Quotation::Cust_FName.length() &lt;= 1)
      ValidCustDetails = false;
    else
    {
      // Error line 165!
      for (unsigned short i = 0; i &lt;= Cust_FName.length; i++)
        if (!isalpha(Quotation::Cust_FName.at(i)))
          ValidCustDetails = false;
    }
    cin.ignore();
    cout &lt;&lt; "\t\tLast Name:";
    getline (cin, Cust_LName, '\n');
    if (Cust_LName.length () &lt;= 1)
      ValidCustDetails = false;
    else
    {
      // Error line 177!
      for (unsigned short i = 0; i &lt;= Cust_LName.length; i++)
        if (!isalpha(Cust_LName.at(i)))
          ValidCustDetails = false;
    }
    cin.ignore();
  }
  while(!ValidCustDetails);
  </code></pre>