c# - System.DBNull to String error in excel -


i have own custom file type similar .csv except custom delimiters. delimiter comma (char)20 (looks square) , quotes (char)254 (looks þ). have created excel 2010 add-in in visual studio parse through document replaces custom delimiters commas , double-quotes in .csv format.

the program creates new toolbar , button start process. works fine on documents not on others , if try twice in 1 instance of excel comes error "cannot implicitly convert type 'system.dbnull' 'string'". because row.text property being read {}.

now question causing row.text property read {} instead of text inside cell? why occur on documents not others though use same encoding?

an example of in cell (note-the comma symbol won't print here):

þitem_idþþbegdocþþenddocþþbegattþþendattþþparent_attachmentþþattachment_batesþþ etc.

edit here code:

    public partial class thisaddin {     office.commandbarbutton toolbarcommand;      private void thisaddin_startup(object sender, system.eventargs e)     {         office.commandbar toolbar = application.commandbars.add("my toolbar",office.msobarposition.msobartop,false,true);         toolbarcommand = (office.commandbarbutton)         toolbar.controls.add(            office.msocontroltype.msocontrolbutton,            missing,            missing,            missing,            true);         toolbarcommand.caption = "toolbar button";         toolbarcommand.faceid = 59;         toolbarcommand.click += new office._commandbarbuttonevents_clickeventhandler(toolbarcommand_click);         toolbar.visible = true;     }        void toolbarcommand_click(office.commandbarbutton ctrl, ref bool canceldefault)     {         excel.worksheet activeworksheet = ((excel.worksheet)application.activesheet);         try         {             iteraterows(activeworksheet);         }         catch(exception e)         {             messagebox.show(e.tostring());         }         ctrl.click+=new office._commandbarbuttonevents_clickeventhandler(toolbarcommand_click);     }      public void iteraterows(excel.worksheet worksheet)     {         //get used range         excel.range usedrange = worksheet.usedrange;          excel.worksheet activeworksheet = ((excel.worksheet)application.activesheet);          //iterate rows in used range          if (usedrange.rows.count > 1)         {             foreach (excel.range row in usedrange.rows)             {                 //messagebox.show(row.text);                 char quote = (char)254;                 string data = row.text;                 row.columns[1] = data.replace(quote, '"').replace((char)20, ',');                 row.texttocolumns(type.missing, excel.xltextparsingtype.xldelimited, excel.xltextqualifier.xltextqualifierdoublequote, type.missing, type.missing, type.missing, true);             }         }     }


Comments

Post a Comment

Popular posts from this blog

curl - PHP fsockopen help required -

i trying work on cloudflare api , have found in documentation. unfortunately have no idea how can use in fsockopen or through curl. here example of post request. need know how can make request below data post using curl or fsockopen curl https://www.cloudflare.com/api_json.html -d 'a=cache_lvl' \ -d 'tkn=8afbe6dea02407989af4dd4c97bb6e25' \ -d 'email=sample@example.com' \ -d 'z=example.com' \ -d 'v=agg' here link cloudflare https://www.cloudflare.com/docs/client-api.html#s4.2 try one: $ch = curl_init("https://www.cloudflare.com/api_json.html"); curl_setopt($ch, curlopt_returntransfer,1); curl_setopt($ch, curlopt_followlocation, 1); curl_setopt($ch, curlopt_ssl_verifypeer,false); // handling of -d curl parameter here. $param = array( 'a' => 'cache_lvl', 'tkn' => '8afbe6dea02407989af4dd4c97bb6e25', 'email' => 'sample@example.com', 'z' =...
Read more

HTTP/1.0 407 Proxy Authentication Required PHP -

i working in restricted network/limited access internet. since have use proxy make web service call. here php code calling web service , response . $client = new soapclient("http: //www.xyz.com/abc/wsdls/login.wsdl", array("trace" => 1, "exceptions" => 1, 'proxy_host' => $proxy_host, 'proxy_port' => $proxy_port, 'proxy_login' => $proxy_login, 'proxy_password' => $proxy_password)); response is fatal error: uncaught soapfault exception: [wsdl] soap-error: parsing wsdl: couldn't load ' http://www.xyz.com/abc/wsdls/login.wsdl ' : failed load external entity if copy url error message , paste in browser(with same proxy settings) works. 2nd scenario is, if pass values instead of variables giving me diffarant response $client = new soapclient("http: //www.xyz.com/abc/wsdls/login.wsdl", array("trace" => 1, "exceptions" => 1, 'proxy_host' ...
Read more

c# - Resource not found error -

i have problem accessing method on homecontroller. show code of method : [httpget] public actionresult decriptidentifiantetredirige(string login_crypter, string mdp_crypter) { string loginacrypter = _globalmanager.protegemotdepasse(login_crypter); string mdpacrypter = _globalmanager.protegemotdepasse(mdp_crypter); user userapp = new models.user(login_crypter, mdp_crypter); if (userapp.authentificationvalidee(userapp.userlogin, userapp.password)) { session["name"] = userapp.userlogin; return redirecttoaction("accueil", "home"); } else { return redirecttoaction("validerauthentification", "home"); } } then in routeconfig.cs wrote route : routes.maproute( name: "authentificationapresdecryptage", url: "{controller}/{action}/{login_crypter}/{mdp_crypter}", defaults: new...
Read more