<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Language" content="en-us"> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <meta name="GENERATOR" content="Microsoft FrontPage 6.0"> <meta name="ProgId" content="FrontPage.Editor.Document"> <title>Boost Escaped List Separator</title> </head> <body bgcolor="#FFFFFF" text="#000000" link="#0000EE" vlink="#551A8B" alink= "#FF0000"> <h1 align="left"><img src="../../boost.png" alt="C++ Boost" width="277" height="86"></h1> <h1 align="center">Escaped List Separator</h1> <div align="left"> <pre> escaped_list_separator<Char, Traits = std::char_traits<Char> > </pre> </div> <p>The <tt>escaped_list_separator</tt> class is an implementation of the <a href="tokenizerfunction.htm">TokenizerFunction</a>. The escaped_list_separator parses a superset of the csv (comma separated value) format. The examples of this formate are below. It is assumed that the default characters for separator, quote, and escape are used.</p> <p>Field 1,Field 2,Field 3<br> Field 1,"Field 2, with comma",Field 3<br> Field 1,Field 2 with \"embedded quote\",Field 3<br> Field 1, Field 2 with \n new line,Field 3<br> Field 1, Field 2 with embedded \\ ,Field 3</p> <p>Fields are normally separated by commas. If you want to put a comma in a field, you need to put quotes around it. Also 3 escape sequences are supported</p> <table border="1" summary=""> <tr> <td> <p align="center"><strong>Escape Sequence</strong></p> </td> <td> <p align="center"><strong>Result</strong></p> </td> </tr> <tr> <td><escape><quote></td> <td><quote></td> </tr> <tr> <td><escape>n</td> <td>newline</td> </tr> <tr> <td><escape><escape></td> <td><escape></td> </tr> </table> <p>Where <quote> is any character specified to be a quote and<escape> is any character specified to be an escape character.</p> <h2>Example</h2> <pre> // simple_example_2.cpp #include<iostream> #include<boost/tokenizer.hpp> #include<string> int main(){ using namespace std; using namespace boost; string s = "Field 1,\"putting quotes around fields, allows commas\",Field 3"; tokenizer<escaped_list_separator<char> > tok(s); for(tokenizer<escaped_list_separator<char> >::iterator beg=tok.begin(); beg!=tok.end();++beg){ cout << *beg << "\n"; } } </pre> <p> </p> <h2>Construction and Usage</h2> <p>escaped_list_separator has 2 constructors. They are as follows</p> <pre> explicit escaped_list_separator(Char e = '\\', Char c = ',',Char q = '\"') </pre> <table border="1" summary=""> <tr> <td> <p align="center"><strong>Parameter</strong></p> </td> <td> <p align="center"><strong>Description</strong></p> </td> </tr> <tr> <td>e</td> <td>Specifies the character to use for escape sequences. It defaults to the C style \ (backslash). However you can override by passing in a different character. An example of when you might want to do this is when you have many fields which are Windows style filenames. Instead of escaping out each \ in the path, you can change the escape to something else.</td> </tr> <tr> <td>c</td> <td>Specifies the character to use to separate the fields</td> </tr> <tr> <td>q</td> <td>Specifies the character to use for the quote.</td> </tr> </table> <p> </p> <pre> escaped_list_separator(string_type e, string_type c, string_type q): </pre> <table border="1" summary=""> <tr> <td> <p align="center"><strong>Parameter</strong></p> </td> <td> <p align="center"><strong>Description</strong></p> </td> </tr> <tr> <td>e</td> <td>Any character in the string e, is considered to be an escape character. If an empty string is given, then there are no escape characters.</td> </tr> <tr> <td>c</td> <td>Any character in the string c, is considered to be a separator. If an empty string is given, then there are no separator characters.</td> </tr> <tr> <td>q</td> <td>Any character in the string q, is considered to be a quote. If an empty string is given, then there are no quote characters.</td> </tr> </table> <p> </p> <p>To use this class, pass an object of it anywhere in the Tokenizer package where a TokenizerFunction is required.</p> <p> </p> <h2>Template Parameters</h2> <table border="1" summary=""> <tr> <th><strong>Parameter</strong></th> <th><strong>Description</strong></th> </tr> <tr> <td><tt>Char</tt></td> <td>The type of the elements within a token, typically <tt>char</tt>.</td> </tr> <tr> <td>Traits</td> <td>The traits class for the Char type. This is used for comparing Char's. It defaults to std::char_traits<Char></td> </tr> </table> <p> </p> <h2>Model of</h2> <p><a href="tokenizerfunction.htm">TokenizerFunction</a></p> <p> </p> <hr> <p><a href="http://validator.w3.org/check?uri=referer"><img border="0" src= "../../doc/images/valid-html401.png" alt="Valid HTML 4.01 Transitional" height="31" width="88"></a></p> <p>Revised <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->25 December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38518" --></p> <p><i>Copyright © 2001 John R. Bandela</i></p> <p><i>Distributed under the Boost Software License, Version 1.0. (See accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or copy at <a href= "http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p> </body> </html>