I have a customer email handler class that takes email messages and does some actions.  One of the things it does is create a comment on the appropriate case with the body of the email included.

The comment that it creates contains some language pertaining to the email, when it was received, the source, and a list of any attachments included.  I have set the piece the code up to automatically reduce the length of the comment to fall well within the 4000 character limit, but for some reason the code is still throwing errors when emails are received that are too long.

Here is a snippet of the code:
        string commentBody;       
        commentBody += 'Email Subject:  ' + email.subject + ' \r\n';    
        commentBody +=  ' \r\n';
        commentBody +=  'Email Body:  ' + ' \r\n';
        if(email.plainTextBody.length() > 3500){
         commentBody = commentBody + email.plainTextBody.trim().left(3500)+ '\r\n' + '\r\n' + '**NOTE: EMAIL BODY TRUNCATED IN COMMENT. SEE EMAIL ATTACHED TO CASE FOR FULL TEXT**';         
        }else{
         commentBody += email.plainTextBody.trim();
        }     
        if(fileAttachmentNames.size() > 0){
            string attachmentsText;
            attachmentsText += ' \r\n';
            attachmentsText += ' \r\n';
            attachmentsText += 'Attachments received:  ';           
            For(String faName :fileAttachmentNames){
                attachmentsText += ' \r\n';
                attachmentsText += faName;
            }
            commentBody = commentBody.left(3500 - attachmentsText.length());
            commentBody += attachmentsText;
        }
       
        newComment.CommentBody = commentBody.trim();
        insert newComment;

However, as I am using the left() method to reduce the length of the comment to 3500 characters I am still getting this error when the email is too long:
"System.DmlException: Insert failed. First exception on row 0; first error: STRING_TOO_LONG, Body: data value too large:"  The error is being thrown on the INSERT line, not before so it is acting like the comment body is too long or something.  Is it possible that the left() method is ignoring HTML values in the string or something?  What other methods should I use to help make sure that the comment stays within the 4000 character limit?
 

Thanks,

Jeremy Stender