Matching literal (normal) text characters with Regular Expressions

Basically regex are used to search a character, word, string or string pattern. Here we are going to search for a single literal character. Consider we want search for "o" in the string patter "Poonam like mango". It will match the "o" after the "P". The default behavior of most regular expression engines is to return just the first match. Though this regex can match the second "o" too. Most regex implementations provide a mechanism by which we can obtain a list of all matches when the regex engine start searching through the string after the first match.

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What is Regular expression engines

The primry work of searching any regular expression pattern is done by Regular expression engines. Regular expression engines have differences based on their type and way of there working. There are mainly two Regular expression engines: Deterministic Finite Automaton (DFA) and Nondeterministic Finite Automaton (NFA). DFAs are faster, but lack many of the features of an NFA, such as capturing, look around, and non greedy quantifiers. The NFA further categories in two sub types: traditional NFA and POSIX.

Deterministic Finite Automaton (DFA) regex engines

DFAs compare each character of the input string to the regular expression, keeping track of all matches in progress. Since each character is examined at most once, the DFA engine is the fastest.

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What is Regular Expressions, an Introduction to Regular Expressions

Regular expressions(or regex) are a language used for more sophisticated form and text processing. They are often used to perform complex search-and-replace operations, and to validate that text data is well-formed. Regular expressions can be used to perform all sorts of powerful text processing and manipulation in just about every language and on every platform. Every regular expression either matches text (search) or matches and replaces text (search and replace).

Today, regular expressions are supported by most programming languages, as well as many scripting languages (like Perl, ASP, Visual Basic, .NET, C#, Java, JSP, PHP,Python, ColdFusion, Tcl, Ruby and many other languages), editors (EmEditor, TextPad), applications (Microsoft Word, Microsoft Excel, StarOffice, OpenOffice), databases(MySQL, SQL Server), and command-line tools.

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JavaScript Auto filling data for ASP.NET web forms with data lock

When we go for shopping online, we purchase any item say CD, Books and place order. To ship our order company ask for our billing as well as shipping address. If we going to gift that item to anyone then both addresses will be different else will same. For same billing and shipping address shopping cart gives us an option. By clicking (checking/selecting) it our billing address content get fill in shipping address field which save our time to retype same address again.
All the process of auto filling data is done by JavaScript. Here we are going to design JavaScript Auto filling data for ASP.NET web forms. Also we are going to lock those fields as we simply coping data from one data field to other.
Working and coding of any JavaScript which get applied on web forms is based on design of form. So first of all we design a web form in ASP.NET. You can design form depending upon data you want from user. Create new ASP.NET web site and design your form. Here I have used dummy form for representation which looks as follows.

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XML Uses and Advantage

Uses and Advantages of XML are:

• XML is a meta-markup language that enables the creation of markup languages for particular documents and domains.
• XML tags describe the structure and semantics of a document’s content, not the format of the content. The format is described in a separate style sheet.
• XML documents are created in an editor, read by a Parser, and displayed by a browser.
• XML on the Web rests on the foundations provided by HTML, CSS, and URLs.
• Numerous supporting technologies layer on top of XML, including XSL style sheets, XLinks, and XPointers. These let you do more than you can accomplish with just CSS and URLs.
• XML tags are not pre-defined. You must define your own tags which provide more flexibility.
• RSS (Really Simple Syndication) Syndicated web site updates (news feeds and blog entries, for example)
• SOAP (Simple Object Access Protocol) Distributed application communication.
• WSDL (Web Services Description Language) Web services
• Open Document, Open file format for office applications (word processing, spreadsheet, and so on)

All of these markup languages are for metadata, but SGML and XML may be further considered meta-languages, since they can be used to create other metadata languages.