Retrieve value from SPFieldMultiLineText field in SharePoint

SPSite site = new SPSite("http://{yoursite}")) 
       { 
         using (SPWeb web = site.OpenWeb()) 
         { 
 
           SPList list = web.Lists["{YourList}"]; 
           SPListItem result = list.GetItemById(1);
SPFieldMultiLineText commentsField = result.Fields.GetField("Comments") as SPFieldMultiLineText; 
 
           string comments = commentsField .GetFieldValueAsText(result["Comments"]); 
           string commentsAsHtml = commentsField .GetFieldValueAsHtml(result["Comments"]); 
}
}

How to get a SPfolder based on FolderId

using (SPSite site = new SPSite("http://localhost"))
     {
      using (SPWeb web = site.OpenWeb())
      {
          
            // Get a folder by server-relative URL.
            string url = web.ServerRelativeUrl + "/shared documents/myfolder";
            SPFolder folder = web.GetFolder(url);

            try
            {
              
              Guid id = folder.UniqueId;              

              // Get a folder by Guid.
              folder = web.GetFolder(id);
              
              }
            catch (Exception ex)
            {
              
            }
         }
     }

Renaming the url of a document library

In SharePoint renaming a document library does not rename the url of the library. That’s how it is..

Having said that you can change the url of the document library by following the steps mentioned below

1.Open your site in SharePoint designer

2.It will list down all the lists/document libraries on the left hand side.

3.Highlight the document library in question

4.Click Rename (What ever you wish to…)to change the document library’s url

Renaming this way also changes the url of the library.