win universal app - Marshal.GetLastWin32Error() throws Access Denied in UWP C# -

-

i have below code in uwp app

public static class deviceiocontrolhelper     { [dllimport("kernel32.dll", setlasterror = true, charset = charset.ansi)]         private static extern safefilehandle createfile(            string lpfilename,            [marshalas(unmanagedtype.u4)] fileaccess dwdesiredaccess,            [marshalas(unmanagedtype.u4)] fileshare dwsharemode,            intptr lpsecurityattributes,            [marshalas(unmanagedtype.u4)] filemode dwcreationdisposition,            [marshalas(unmanagedtype.u4)] fileattributes dwflagsandattributes,            intptr htemplatefile);  public static safefilehandle returnfilehandler()         {             const string drive = @"\\.\lcd";              safefilehandle hddhandle = createfile(drive, fileaccess.read, fileshare.none, intptr.zero, filemode.open, fileattributes.normal, intptr.zero);              if (hddhandle.isinvalid)             {                 int lasterror = marshal.getlastwin32error();                 string errormessage = string.format(@"!! invalid {0}; error ({1}): {2}", drive, lasterror, new win32exception(lasterror).message);                 throw new win32exception(errormessage);             }              return hddhandle;         } }

but, when try access mainpage.xaml.cs, got expcetion of "access denied". switching visual studio 2015 community admin mode did not helped either

public sealed partial class mainpage : page     {         public mainpage()         {             this.initializecomponent();              try             {                 deviceiocontrolhelper.returnfilehandler();             }             catch(exception ex)             {              }         } }

i using uwp c# in visual studio 2015 community

you need use createfile2 open files universal windows application. won't allow open devices, though. quote msdn: when called windows store app, createfile2 simplified. can open files or directories inside applicationdata.localfolder or package.installedlocation directories.


Comments

Post a Comment

Popular posts from this blog

java - nested exception is org.hibernate.exception.SQLGrammarException: could not extract ResultSet Hibernate+SpringMVC -

-
i trying fetch records database , having above error this classs appropriate getters , setters public class user { private int id; private string username; private string password; private string email; i have create database , inserted data below configuration <bean id="datasource" class="org.apache.commons.dbcp2.basicdatasource" destroy-method="close"> <property name="driverclassname" value="com.mysql.jdbc.driver"/> <property name="url" value="jdbc:mysql://localhost:3306/usersdb"/> <property name="username" value="root"/> <property name="password" value=""/> </bean> this complete stacktrace severe: servlet.service() servlet [appservlet] in context path [/spring] threw exception [request processing failed; nested exception org.hibernate.exception.sqlgrammarexception: not ...
Read more

sql - Postgresql tables exists, but getting "relation does not exist" when querying -

-
Image
i have postgresql db number of tables. if query: select column_name information_schema.columns table_name="my_table"; i list of columns returned properly. however, when query: select * "my_table"; i error: (programmingerror) relation "my_table" not exist 'select *\n "my_table"\n' {} any thoughts on why can columns, can't query table? goal able query table. you have include schema if isnt public one select * <schema>."my_table" or can change default schema show search_path; set search_path my_schema; check table schema here select * information_schema.columns for example if table on default schema public both works ok select * parroquias_region select * public.parroquias_region but sectors need specify schema select * map_update.sectores_point
Read more

asp.net mvc - breakpoint on javascript in CSHTML? -

-
i have .cshtml file has javascript tag. within script tag have few lines of javascript. first line of javascript refers property in @viewbag. other javascript lines plain script without mvc related references. observation: can place breakpoints (visual studio 2015) on each of these javascript lines. however, breakpoints has white dot in center of breakpoint symbol (red circle) except line @viewbag reference (this particular line not have white dot in center). it seems breakpoint without white dot hit during run-time. question: can explain going on here? white dot mean? why plain red breakpoint line line hitting breakpoint? the visual studio debugger expecting debug actual server-side code within .cshtml file opposed client-side javascript within it. iirc, visual studio allow debug javascript code expected in internet explorer (and possibly edge), other browsers want use either third-party tool or developer tools (f12) within browser. an easy approach take advant...
Read more