1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 2 3<html> 4<head> 5 <meta http-equiv="Content-Language" content="en-us"> 6 <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> 7 <meta name="GENERATOR" content="Microsoft FrontPage 6.0"> 8 <meta name="ProgId" content="FrontPage.Editor.Document"> 9 10 <title>Boost Escaped List Separator</title> 11</head> 12 13<body bgcolor="#FFFFFF" text="#000000" link="#0000EE" vlink="#551A8B" alink= 14"#FF0000"> 15 <h1 align="left"><img src="../../../boost.png" alt="C++ Boost" width="277" 16 height="86"></h1> 17 18 <h1 align="center">Escaped List Separator</h1> 19 20 <div align="left"> 21 <pre> 22escaped_list_separator<Char, Traits = std::char_traits<Char> > 23</pre> 24 </div> 25 26 <p>The <tt>escaped_list_separator</tt> class is an implementation of the 27 <a href="tokenizerfunction.htm">TokenizerFunction</a>. The 28 escaped_list_separator parses a superset of the csv (comma separated value) 29 format. The examples of this formate are below. It is assumed that the 30 default characters for separator, quote, and escape are used.</p> 31 32 <p>Field 1,Field 2,Field 3<br> 33 Field 1,"Field 2, with comma",Field 3<br> 34 Field 1,Field 2 with \"embedded quote\",Field 3<br> 35 Field 1, Field 2 with \n new line,Field 3<br> 36 Field 1, Field 2 with embedded \\ ,Field 3</p> 37 38 <p>Fields are normally separated by commas. If you want to put a comma in a 39 field, you need to put quotes around it. Also 3 escape sequences are 40 supported</p> 41 42 <table border="1" summary=""> 43 <tr> 44 <td> 45 <p align="center"><strong>Escape Sequence</strong></p> 46 </td> 47 48 <td> 49 <p align="center"><strong>Result</strong></p> 50 </td> 51 </tr> 52 53 <tr> 54 <td><escape><quote></td> 55 56 <td><quote></td> 57 </tr> 58 59 <tr> 60 <td><escape>n</td> 61 62 <td>newline</td> 63 </tr> 64 65 <tr> 66 <td><escape><escape></td> 67 68 <td><escape></td> 69 </tr> 70 </table> 71 72 <p>Where <quote> is any character specified to be a quote 73 and<escape> is any character specified to be an escape character.</p> 74 75 <h2>Example</h2> 76 <pre> 77// simple_example_2.cpp 78#include<iostream> 79#include<boost/tokenizer.hpp> 80#include<string> 81 82int main(){ 83 using namespace std; 84 using namespace boost; 85 string s = "Field 1,\"putting quotes around fields, allows commas\",Field 3"; 86 tokenizer<escaped_list_separator<char> > tok(s); 87 for(tokenizer<escaped_list_separator<char> >::iterator beg=tok.begin(); beg!=tok.end();++beg){ 88 cout << *beg << "\n"; 89 } 90} 91</pre> 92 93 <p> </p> 94 95 <h2>Construction and Usage</h2> 96 97 <p>escaped_list_separator has 2 constructors. They are as follows</p> 98 <pre> 99explicit escaped_list_separator(Char e = '\\', Char c = ',',Char q = '\"') 100</pre> 101 102 <table border="1" summary=""> 103 <tr> 104 <td> 105 <p align="center"><strong>Parameter</strong></p> 106 </td> 107 108 <td> 109 <p align="center"><strong>Description</strong></p> 110 </td> 111 </tr> 112 113 <tr> 114 <td>e</td> 115 116 <td>Specifies the character to use for escape sequences. It defaults to 117 the C style \ (backslash). However you can override by passing in a 118 different character. An example of when you might want to do this is 119 when you have many fields which are Windows style filenames. Instead of 120 escaping out each \ in the path, you can change the escape to something 121 else.</td> 122 </tr> 123 124 <tr> 125 <td>c</td> 126 127 <td>Specifies the character to use to separate the fields</td> 128 </tr> 129 130 <tr> 131 <td>q</td> 132 133 <td>Specifies the character to use for the quote.</td> 134 </tr> 135 </table> 136 137 <p> </p> 138 <pre> 139escaped_list_separator(string_type e, string_type c, string_type q): 140</pre> 141 142 <table border="1" summary=""> 143 <tr> 144 <td> 145 <p align="center"><strong>Parameter</strong></p> 146 </td> 147 148 <td> 149 <p align="center"><strong>Description</strong></p> 150 </td> 151 </tr> 152 153 <tr> 154 <td>e</td> 155 156 <td>Any character in the string e, is considered to be an escape 157 character. If an empty string is given, then there are no escape 158 characters.</td> 159 </tr> 160 161 <tr> 162 <td>c</td> 163 164 <td>Any character in the string c, is considered to be a separator. If 165 an empty string is given, then there are no separator characters.</td> 166 </tr> 167 168 <tr> 169 <td>q</td> 170 171 <td>Any character in the string q, is considered to be a quote. If an 172 empty string is given, then there are no quote characters.</td> 173 </tr> 174 </table> 175 176 <p> </p> 177 178 <p>To use this class, pass an object of it anywhere in the Tokenizer 179 package where a TokenizerFunction is required.</p> 180 181 <p> </p> 182 183 <h2>Template Parameters</h2> 184 185 <table border="1" summary=""> 186 <tr> 187 <th><strong>Parameter</strong></th> 188 189 <th><strong>Description</strong></th> 190 </tr> 191 192 <tr> 193 <td><tt>Char</tt></td> 194 195 <td>The type of the elements within a token, typically 196 <tt>char</tt>.</td> 197 </tr> 198 199 <tr> 200 <td>Traits</td> 201 202 <td>The traits class for the Char type. This is used for comparing 203 Char's. It defaults to std::char_traits<Char></td> 204 </tr> 205 </table> 206 207 <p> </p> 208 209 <h2>Model of</h2> 210 211 <p><a href="tokenizerfunction.htm">TokenizerFunction</a></p> 212 213 <p> </p> 214 <hr> 215 216 <p><a href="http://validator.w3.org/check?uri=referer"><img border="0" src= 217 "../../doc/images/valid-html401.png" alt="Valid HTML 4.01 Transitional" 218 height="31" width="88"></a></p> 219 220 <p>Revised 221 <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->25 222 December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38518" --></p> 223 224 <p><i>Copyright © 2001 John R. Bandela</i></p> 225 226 <p><i>Distributed under the Boost Software License, Version 1.0. (See 227 accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or 228 copy at <a href= 229 "http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p> 230</body> 231</html> 232
