How Do I Solve Object Reference Not Set To An Instance Of An Object.

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Am trying to loop through xmlnodes. but getting this error "Object reference not set to an instance of an object." My main goal was to loop it through the datgridviewcell but i don't know how i can take it further. I know the column indexes for font,date and comment from my grid. how can i loop through those column indexes and be able to parse the value to string?

My code
<root> <value> <comment>[Font]Bold[/Font][DateStamp][/DateStamp][Comment][/Comment]

Font is index 2 from my datagridview
DateStamp is index 3 from my datagridview
Comment is index 4 from my datagridview

C#

XmlNodeList _Nodelist = _doc.SelectNodes("/root");
               foreach(XmlNode _Xnode in _Nodelist)
               {
                   XmlNode _data = _Xnode.SelectSingleNode("data");
                   XmlNodeList _CommentNodes = _data.SelectNodes("comment");
                   if(_CommentNodes != null)
                   {
                       foreach(XmlNode node in _CommentNodes)
                       {
                           XmlNode _comment = node.SelectSingleNode("comment");
                           {

                                   string _font = _comment["Font"].InnerText; //it throws the error here
                                   string _Date = _comment["DateStamp"].InnerText;
                                   string _Comment = _comment["Comment"].InnerText;
                           }
                       }
                   }
               }

Posted 24-Feb-15 23:35pm

Bacanzela

Updated 24-Feb-15 23:50pm

RajeeshMenoth

v3

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2 solutions

Solution 1

If your comment is correct, then _comment["Font"] in that line must be null. Trying to access the InnerText property leads to the exception.

There are unneeded brackets after this line:
XmlNode _comment = node.SelectSingleNode("comment");

Could those brackets belong to a if(_comment != null), which somehow got lost?

Also, you will have to individually test wether or not _comment["Font"], _comment["DateStamp"] or _comment["Comment"] really exist (are not null) before accessing any of their properties.

Posted 24-Feb-15 23:56pm

CDP1802

Updated 24-Feb-15 23:59pm

v2

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Himanshu Kumarrrr · Accepted Answer · 2015-02-25T02:04:00

Solution 2

This error is because of _comment["Font"] is null.

Check _comment["Font"] is not null.
Put if condition here like below

if(null!=_comment["Font"])
{
string _font = _comment["Font"].InnerText;
}

It will work for sure. :)

Posted 25-Feb-15 2:04am

Himanshu Kumarrrr

Comments

[no name] 25-Feb-15 10:05am

It will work for sure? I would like to see your face when the following two lines cause the whole thing to fall flat on its face again after your 'working for sure' correction.

Bacanzela 26-Feb-15 7:59am

Thanks!