Frederick Chapleau .NET Tip of the Day

A generic way to call ExecuteScalar

Frederick.Chapleau — Fri, 05 Feb 2010 12:16:38 GMT

When calling execute Scalar, we always begin by calling it with some code like

int i = cmd.ExecuteScalar();

What’s wrong with this picture?… what if, the first field of the first row is… NULL?

so…

int i;
object o = cmd.ExecuteScalar();
if(o != null)
i = (int)o;

-f.

Multi Line string in C#

Frederick.Chapleau — Tue, 02 Feb 2010 15:57:49 GMT

Ever wonder of a more efficient way to write multiple lines strings?

Check this out…

The first way...

string myString1 = "This is the first line of my string.\n" +
                   "This is the second line of my string.\n" +
                   "This is the third line of the string.\n";

And a more efficient way...


string myString2 = @"This is the first line of my string.
This is the second line of my string.
This is the third line of the string.";

-f.

Usage of static constant for SQL Statements

Frederick.Chapleau — Mon, 01 Feb 2010 18:01:00 GMT

Embedding SQL statement is sometimes useful. A good practice is to centralize them in a class, using public constants...

public const string SQL_MYTABLE_INSERT = "INSERT MYTABLE (FIELD) VALUES (@FIELDVALUE)";

-f.

WebService Prefix

Frederick.Chapleau — Wed, 27 Jan 2010 15:23:46 GMT

When adding a web service to your 2.0 .NET project, always begin by the same prefix, so, when the code will be generated, the namespace using will always be the same... like WebService.TheWSName and WebService.TheSecondWSName...

-f.

Use internal instead of public

Frederick.Chapleau — Mon, 04 Jan 2010 12:42:37 GMT

For production product, usage of public should be only used for publicly accessible methods, because all public methods can be used by other assembly/application than yours.

-f.

The params keyword, when a single argument is not enough

Frederick.Chapleau — Tue, 28 Jul 2009 03:53:00 GMT

When you don’t want to provide a fixed number of argument for a method, you can use the params modifier, that can handle a list of values of a single type, instead of requiring from the caller to build a list.

void UseParams(params int[] list)

-f.

ref.: http://msdn.microsoft.com/en-us/library/w5zay9db.aspx

Use always the same standard for exceptions and event

Frederick.Chapleau — Sun, 26 Jul 2009 15:11:00 GMT

e is not enough... usually handle event as an “e”, and exceptions as an “ex”

...sorry, it too obvious ;)

-f.

A new way to handle cleanup

Frederick.Chapleau — Sun, 26 Jul 2009 01:31:00 GMT

You should know about the try{}catch{} block. But did you know that you can use a try{}finally{} block?

So when an error is raised, you are sure that the statements in the finally block are executed.

-f.

Usage of the @

Frederick.Chapleau — Fri, 24 Jul 2009 21:05:00 GMT

In C#, when you have a string with slash in it, you must double it to have a result of only one, because of the escape code.

When starting a string with a @, you can’t insert escape code, but you do not have to double them.

-f.

The 3 Strike Method

Frederick.Chapleau — Thu, 23 Jul 2009 15:40:00 GMT

1. You write it, as good as you think it should be implemented.

2. You realize that it can be better, you can improve it.

3. The last time you touch it, after that it can only be worst.

-f.

Use the String.Format

Frederick.Chapleau — Wed, 22 Jul 2009 12:22:00 GMT

You can a string using a standard.Comparable to the sprintf C format...

-f.

ref.: http://msdn.microsoft.com/en-us/library/system.string.format(VS.71).aspx

Explicitly call Dispose

Frederick.Chapleau — Tue, 21 Jul 2009 19:23:00 GMT

Calling Dispose release resources immediately, that can be useful for big files, handles etc...

-f.

Improve your startup

Frederick.Chapleau — Tue, 21 Jul 2009 03:21:00 GMT

Use SGEN to generate the XML Generation assembly, it can be improved from milliseconds to minutes...

-f.

http://msdn.microsoft.com/en-us/library/bk3w6240(VS.80).aspx

JavaScript Timeout retention

Frederick.Chapleau — Sun, 19 Jul 2009 20:22:00 GMT

Timeout are used since… well… since the dynamic web exists. But the returned timeout variable (usally a number) can be used to stop them. A good hint is to always store it somewhere, so that you can easily cancel them later.

-f.

CSS Z-Index

Frederick.Chapleau — Sat, 18 Jul 2009 23:19:00 GMT

A great layout tips... Overlay!

The Zindex CSS property can priories the layout order. A kind of Bring Forward and Send to Back.

-f.