Compiler Error Cs0165
Contents |
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss error cs0165 use of unassigned local variable the workings and policies of this site About Us Learn more about
Error Cs0165 C#
Stack Overflow the company Business Learn more about hiring developers or posting ads with us Stack Overflow
Error Use Of Unassigned Local Variable C#
Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each
Use Of Unassigned Local Variable C# Array
other. Join them; it only takes a minute: Sign up C# error CS0165: Use of unassigned local variable - ignoring logic and out reference up vote 2 down vote favorite After searching around I cant seem to locate why the C# compiler is complaining that the local variable dteDest is unassigned in the line if (dteSrc == dteDest) { use of unassigned local variable c# string The error goes away if I replace the line DateTime dteSrc, dteDest; with DateTime dteSrc, dteDest = DateTime.MinValue; As far as I can see the code will never reach the comparison line if dteDest is not initialised by the DateTime.TryParse which it is an out parameter for. My logic is: If currentDataObj is null then booHaveOrigDate is false and the first if fails If currentDataObj is not null but cant be converted to a DateTime then booHaveOrigDate is false and the first if fails DateTime.TryParse will return false if it cant convert to a DateTime this along with the && means that dteDest will never be used. Simple Sample Code void StrangeLogic(object srcData, object currentDataObj) { DateTime dteSrc, dteDest; bool booHaveNewDate = DateTime.TryParse(srcData.ToString(), out dteSrc); bool booHaveOrigDate = (currentDataObj != null) && DateTime.TryParse(currentDataObj.ToString(), out dteDest); if (booHaveNewDate && booHaveOrigDate) { if (dteSrc == dteDest) { // Get a "use of unassignned local variable 'dteDest' // unless dteDest = DateTime.MinValue beforehand } } } Also if I change the line bool booHaveNewDate = DateTime.Try
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about how to fix use of unassigned local variable in c# hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask use of unassigned local variable datetime c# Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join use of unassigned local variable c# if statement them; it only takes a minute: Sign up Why compile error “Use of unassigned local variable”? up vote 27 down vote favorite 5 My code is the following int tmpCnt; if (name == "Dude") tmpCnt++; Why is there an http://stackoverflow.com/questions/7900635/c-sharp-error-cs0165-use-of-unassigned-local-variable-ignoring-logic-and-out error Use of unassigned local variable tmpCnt? I know I didn't explicitly initialize it but due to Default Value Table a value type is initialized with 0 anyways. The reference also reminds me: Remember that using uninitialized variables in C# is not allowed. But why do I have to do it explicitly if it's already done by default? Wouldn't it gain performance if I wouldn't have to do it? Just wondering... c# .net compiler-construction share|improve this question asked http://stackoverflow.com/questions/9233000/why-compile-error-use-of-unassigned-local-variable Feb 10 '12 at 18:41 theknut 59521231 Can anyone help me with the headline? Couldn't find a fitting for this one :-S –theknut Feb 10 '12 at 18:44 I have a local struct, never initialized, compiles with no errors. Today I created a different struct, treated identically, got "uninitialized local variable error". All its members were set to a value before use, but I could not first set it to null, since it was 'just' a struct. The struct that compiled contained only ints, bools and strings. The one that gave the error also contained DateTimes. "MyStructType myStruct = new MyStructType();" killed the error. Not the first time I've been bitten by missing something a few levels down. –mickeyf Jun 2 at 19:14 add a comment| 9 Answers 9 active oldest votes up vote 55 down vote accepted Local variables aren't initialized. You have to manually initialize them. Members are initialized, for example: public class X { private int _tmpCnt; // This WILL initialize to zero ... } But local variables are not: public static void SomeMethod() { int tmpCnt; // This is not initialized and must be assigned before used. ... } So your code must be: int tmpCnt = 0; if (name == "Dude") tmpCnt++; So the long and the short of it is, members are initialized, locals are not. That is why you get the compiler error
Support Search GitHub This repository Watch 886 Star 6,315 Fork 1,515 dotnet/roslyn Code Issues 3,177 Pull requests 133 Projects 0 Wiki Pulse Graphs New issue "Use of unassigned https://github.com/dotnet/roslyn/issues/4272 local variable" CS0165 issue #4272 Closed mpmel opened this Issue Jul 31, 2015 · 6 comments Projects None yet Labels Area-Compilers Resolution-By Design Milestone No milestone Assignees No one assigned 5 participants mpmel https://books.google.com/books?id=A-vzSC3zhqMC&pg=PA114&lpg=PA114&dq=compiler+error+cs0165&source=bl&ots=kf1I_gLgGL&sig=PUVtI6BKp-XAGY5NfOlXEJL5RO8&hl=en&sa=X&ved=0ahUKEwjYyOCXrrvPAhXo24MKHeouDxYQ6AEIWTAJ commented Jul 31, 2015 I'm getting a complaint in my code using VS 2015 and .Net 4.5.2, and am not quite understanding why. If I call MyObject o; if (objects != null && use of objects.TryGetValue(objectName, out o)) v.Property= o; then everything is fine. The following two cases however give me an error, and I'm not quite understanding why. MyObject o; if (objects != null ? objects.TryGetValue(objectName, out o) : false) v.Property= o; // <-- error CS0165: Use of Unassigned local variable 'o' and MyObject o; bool b; if (objects != null) b = objects.TryGetValue(objectName, out o); else b = false; use of unassigned if (b) v.Property = o; // <-- error CS0165: Use of Unassigned local variable 'o' In either of the last 2 cases, I don't see how o can be used unless TryGetValue is called, which means o should be initialized. Is this a bug? Or I am I missing something? Pilchie added the Area-Compilers label Jul 31, 2015 paul1956 commented Jul 31, 2015 All the VB examples show an explicate initialization of "o", even though the documentation call value an out or
to read 1,200 pages, Accelerated C# 2008 gives you everything you need to know about C# 2008 in a concentrated 500 pages of must-know information and best practices.C# 2008 offers powerful new features, and Accelerated C# 2008 is the fastest path...https://books.google.ca/books/about/Accelerated_C_2008.html?id=A-vzSC3zhqMC&utm_source=gb-gplus-shareAccelerated C# 2008My libraryHelpAdvanced Book SearchBuy eBook - CA$31.39Get this book in printApress.comAmazon.caChapters.indigo.caFind in a libraryAll sellers»Accelerated C# 2008Trey NashApress, Feb 7, 2008 - Computers - 510 pages 1 Reviewhttps://books.google.ca/books/about/Accelerated_C_2008.html?id=A-vzSC3zhqMCMany books introduce C#, but if you don't have the time to read 1,200 pages, Accelerated C# 2008 gives you everything you need to know about C# 2008 in a concentrated 500 pages of must-know information and best practices.C# 2008 offers powerful new features, and Accelerated C# 2008 is the fastest path to mastery, for both experienced C# programmers moving to C# 2008 and programmers moving to C# from another object-oriented language.You’ll quickly master C# syntax while learning how the CLR simplifies many programming tasks. You’ll also learn best practices that ensure your code will be efficient, reusable, and robust. Why spend months or years discovering the best ways to design and code C# when this book will show you how to do things the right way, right from the start? Comprehensively and concisely explains both C# 2005 and C# 2008 features Focuses on the language itself and on how to use C# 2008 proficiently for all .NET application development Concentrates on how C# features work and how to best use them for robust, high–performance code Preview this book » What people are saying-Write a reviewWe haven't found any reviews in the usual places.Selected pagesTitle PageTable of ContentsIndexReferencesContentsreflection Typically you start with a SystemType object when you 14 C Syntax Overview 17 Classes Structs and Objects 39 Note Encapsulation helps you achieve the ageold guideline of strong 55 Interfaces and Contracts 123 Note Since COM became so popular some developers have a 145 Overloading Operators 149 Note Now wait just a minute some of you from 151 Note In NET 1x the signature of the methods wired 255 Generics 279 Note When creating your own custom collection types you should 286 But this is valid 296