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Posted 22 Oct 2010

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Common Mistakes Made by Programmers

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3.16/5 (21 votes)
22 Oct 2010CPOL1 min read
Common Mistakes Made by Programmers
Introduction

Making mistakes is inevitable in programming. Even a small mistake could prove to be very costly. The wise thing is to learn from your mistakes and try not to repeat them.

In this article I will be highlighting the one of the mistakes which I consider to be the most common mistake made by C# developers.

Formatting a string

There lies the strong possibility of making costly mistakes while working with string types in C# programming. String is always an immutable type in the .NET Framework. When a string is modified it always creates a new copy and never changes the original. Most developers always format the string as shown in the sample below

<br />
string updateQueryText = "UPDATE EmployeeTable SET Name='" + name + "' WHERE EmpId=" + id;<br />
<br />


The above code is really messy and also as the string is immutable it creates 3 unnecessary garbage string copies in the memory as a result of multiple concatenations.

The better approach is to use string.Format as it internally uses StringBuilder which is mutable. It also paves the way for a clean code.

<br />
string updateQueryText = string.Format("UPDATE EmployeeTable SET Name='{0}' WHERE EmpId={1}", name, id);<br />


Keep watching for some more tips....
Eswar

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

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About the Author

TweakBird
Software Developer (Senior)
India India
I have good knowledge on Application Development, Developing components, Participating in design workshops and reviews. Particularly interested in client/server and windows applications. i have working experience with Oracle 10g, 11g, PostgreSQL, and MS-SQL Server Databases.

Comments and Discussions

 
GeneralReason for my vote of 4 nice tip Pin
MessiNRG12-Feb-12 6:03
MemberMessiNRG12-Feb-12 6:03 
GeneralReason for my vote of 4 Good Tip Pin
Sandesh M Patil3-Dec-10 3:31
MemberSandesh M Patil3-Dec-10 3:31 
GeneralReason for my vote of 1 It's a total mistake to concatenate.... Pin
ArchElf27-Oct-10 10:32
MemberArchElf27-Oct-10 10:32 
GeneralReason for my vote of 1 bad sql script Pin
yunusatmaca27-Oct-10 4:51
Memberyunusatmaca27-Oct-10 4:51 
GeneralYes.I completely agree. Pin
GPUToaster™26-Oct-10 23:38
MemberGPUToaster™26-Oct-10 23:38 
Yes.I completely agree.
GeneralReason for my vote of 1 If you're going to demonstrate strin... Pin
Richard Deeming26-Oct-10 9:15
mveRichard Deeming26-Oct-10 9:15 
Generaloops I was meant to say: string text = tbStatic.text + " ... Pin
Blubbo26-Oct-10 4:11
MemberBlubbo26-Oct-10 4:11 
GeneralReason for my vote of 5 Thanks for the tip! I've never used ... Pin
Blubbo26-Oct-10 4:09
MemberBlubbo26-Oct-10 4:09 
GeneralReason for my vote of 1 This is SQL injection waiting to hap... Pin
jim lahey26-Oct-10 3:16
Memberjim lahey26-Oct-10 3:16 
GeneralReason for my vote of 3 Information is not full. It contains... Pin
Anton Kratenok25-Oct-10 23:24
MemberAnton Kratenok25-Oct-10 23:24 
GeneralReason for my vote of 5 practible Pin
Semions25-Oct-10 20:07
MemberSemions25-Oct-10 20:07 
GeneralReason for my vote of 3 If you expect to execute the line of... Pin
dmjm-h25-Oct-10 13:38
Memberdmjm-h25-Oct-10 13:38 
GeneralIt may also be good to mention the StringBuilder.AppendForma... Pin
supercat925-Oct-10 7:10
Membersupercat925-Oct-10 7:10 
GeneralStringBuilder isn't magic. If it has to expand its internal ... Pin
Henry.Ayoola25-Oct-10 4:58
MemberHenry.Ayoola25-Oct-10 4:58 
GeneralReason for my vote of 2 it's a good pract Pin
Herre Kuijpers23-Oct-10 4:18
MemberHerre Kuijpers23-Oct-10 4:18 
Generalmy intension is mainly using string.Format() Method.. we can... Pin
TweakBird23-Oct-10 3:58
MemberTweakBird23-Oct-10 3:58 
Generalsensible to SQL injection. Pin
Hiren solanki22-Oct-10 23:32
MemberHiren solanki22-Oct-10 23:32 
GeneralReason for my vote of 4 Nice use of string.Format Thanks for... Pin
Khaniya22-Oct-10 20:28
professionalKhaniya22-Oct-10 20:28 
GeneralYou must have mist this comic that humorously makes clear wh... Pin
E.F. Nijboer22-Oct-10 12:54
MemberE.F. Nijboer22-Oct-10 12:54 
GeneralReason for my vote of 1 I gave you a 1 because your example ... Pin
SledgeHammer0122-Oct-10 11:09
MemberSledgeHammer0122-Oct-10 11:09 
GeneralReason for my vote of 5 never knew stringbuilder is used ins... Pin
FadiYoosuf22-Oct-10 5:10
MemberFadiYoosuf22-Oct-10 5:10 
GeneralReason for my vote of 4 Thanks for the info. It is really a ... Pin
Sivaraman Dhamodharan22-Oct-10 4:10
MemberSivaraman Dhamodharan22-Oct-10 4:10 

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