IIS For Developers

IIS 7 / 7.5

• Version of IIS is always tied to version of OS.
• Modularity of IIS 7 /7.5: You chose modules of IIS which are to be installed.
• SSL Site: A unique IP address is required for SSL enabled web site.IIS cannot use Host name to distinguish, because host name is encrypted when IIS handles request.
• Starting IIS 7 certain settings are saved in Application’s web.config file.Each App pool has one worker process.
• Starting IIS 7: When you create a new web site, IIS creates a new App pool of exact same name.
• Managed Pipeline mode:  Use Integrated mode if possible.
• Unhandled exceptions lead to App pool to crash.
• Any type of configuration change leads to an App pool to recycle.
• Session state is saved in App pool. So when App pool is recycled session state would be lost?  
• IIS Troubleshooting

                                    -  Find slow running pages in runtime using worker processes module
                                     - Track errors using Failed Request Tracing module

• Log Parser Wizard & Log Parser Tool are could be used to analyze log files. Log Parser Tool allows SQL like queries on log.
• MSDeploy is a tool from Microsoft for deploying web sites.
• MSDeploy could be used

                    - To sync two web servers.

                            - Take back-up of site on physical drive and vice versa.

                            - Since Visual Studio 2010. MSDeploy is built in to VS 2010.

• URL Rewrite extension: Could be used to give friendly URLs to user. This is IIS feature.
• Web Farm Framework: There is IIS extension which helps in Web Farm.

IIS 8

• Application Initialization: When first user shows up, lot of initialization happens. Application initialization allows this to be done before first user shows up. Thus first user won't take hit.
• SNI: Allows multiple SSL certificates to one IP Address.

.Net Regular Expression

Regular Expressions

• With .Net Regex you need to think about efficiency first.

• Regex class supports two flavors of Regular Expressions

1. Full featured .Net version
2. ECMA (JavaScript) version

• Outcome of Regex.Match can tell which part of subject matched which parts of pattern.

• Concatenation, Alternation (|), Repetition (*)

• Regex is immutable class.

• Regex finds leftmost match.

• Alternation: Order of terms in alternation is important (catnip|cat) will match catnip first and if this didn’t match then it will match cat.

• Repetition

1. Group a set of characters together using parenthesis for e.g. (cat)* matches all multiple occurrences of cat.
2.  (cat)* : Match 0 or more
3. (cat)? : Match 0 or 1
4. (cat)+ : Match 1 or more
5. (cat){1, 4}: Minimum 1 and maximum 4 occurrences are to be matched. 

Matching whole Expressions

• Match.NextMatch gives next match.

• (?m) : End modifier. This says that subsequent Regex is multiline regular expression.

• \A : Match start of the string. This is not affected by End modifier.

• ^: Same as \A if regular expression is not multiline. Matches subsequent pattern only at the start of new line.

• $: (Opposite of ^) When regular expression is not multiline, match should end with string end. When regular expression is NOT multiline, match should end with newline.

• \Z: (Opposite of \A) is not affected by End modifier. Match end of string.

• Custom character class e.g. [abc]

• Custom character class is more efficient than alternatives i.e. [abc] is more efficient than a|b|c. That’s why character classes are preferred over alternations if possible.

• Character class matches single character only.

• [a-z0-9] : All characters from a to z and 0 to 9

• [^a-z]: All characters except a to z. ^ is negation in this context.

• /d : [0-9]

• /D: [^0-9] (Note negation, so all characters except 0 to 9.

• /s: Any white space character

• /S: Negation of /s

• /w: a to z, A to Z, 0 to 9 and underscore and few more characters which are part considered to be part of English word

• /W: Negation of /w

• \w{3}: Match exactly 3 word characters

• \ is escape character. Regex.Escape method will add escape characters wherever necessary.

• \b: Word boundary. Matches with start or end of the word.

• \B: Negation of \b

• . (Dot): Wild character. Matches any character. By default won’t match New line.

• (?s) : Dot Modifier. (Dot) will match new line character as well. (:) colon is used to scope modifier to only one alternation pattern. For e.g. (?s: c.t) | d.g : Here modifier is applied only to first clause of the pattern.

• Avoid using operator * on . (dot) for performance reasons.