Introduction

This is a library for parsing text files.

The records could be comma delimited, tab delimited or delimited with any set of characters.

The csv_parser class is used to parse text files to extract records and fields.

We are making the following assumptions :

• The record terminator is only one character in length.
• The field terminator is only one character in length.
• The fields are enclosed by single characters, if any.

• The parser can handle documents where fields are always enclosed, not enclosed at all or optionally enclosed.
• When fields are strictly all enclosed, there is an assumption that any enclosure characters within the field are escaped by placing a backslash in front of the enclosure character.

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The CSV files can be parsed in 3 modes.

• (a) No enclosures
• (b) Fields always enclosed.
• (c) Fields optionally enclosed.

For option (c) when the enclosure character is optional, if an enclosure character is spotted at either the beginning or the end of the string, it is assumed that the field is enclosed.

The csv_parser::init() method can accept a character array as the path to the CSV file. Since it is overloaded, it can also accept a FILE pointer to a stream that is already open for reading.

The set_enclosed_char() method accepts the field enclosure character as the first parameter and the enclosure mode as the second parameter which controls how the text file is going to be parsed.

The source documentation is available here

http://www.israelekpo.com/csv-parser-documentation/

Library Installation

Decompress the tarball

tar -zxvf csv_parser-x.x.tar.gz

cd csv_parser

Configure, compile and install

./configure

make

make all install

Linking and Compiling Source Programs

g++ -Wall -O2 -g csv_parser-config --cxxflags --libs example.cpp -o example

Example Usage

#include <csv_parser/csv_parser.hpp>

/**
 * Example Usage of libcsv_parser++
 *
 * These are some of the characters you may use in this program
 *
 * @li DEC is how it would be represented in decimal form (base 10)
 * @li HEX is how it would be represented in hexadecimal format (base 16)
 *
 * @li	DEC	HEX		Character Name
 * @li	0	0x00	null
 * @li	9	0x09	horizontal tab
 * @li	10	0x0A	line feed, new line
 * @li	13	0x0D	carriage return
 * @li	27	0x1B	escape
 * @li	32	0x20	space
 * @li	33	0x21	double quote
 * @li	39	0x27	single quote
 * @li	44	0x2C	comma
 * @li	92	0x5C	backslash
 */

/**
 * Example Program - showing usage of the csv_parser class
 *
 * In this example, we include the csv_parser header file as <csv_parser/csv_parser.hpp>
 *
 * Then we declare the variables we are going to use in the program
 *
 * @li The name of the input file is "example_input.csv"
 * @li The field terminator is the comma character
 * @li The record terminator is the new line character 0x0A
 * @li The field enclosure character is the double quote.
 *
 * In this example we will be parsing the document as the fields are optionally enclosed.
 *
 * The first record in the CSV file will be skipped.
 *
 * Please view the source code of this file more closely for details.
 *
 * @todo Add more examples using different parsing modes and different enclosure and line terminator characters.
 * @toto Include an example where the filename, field_terminator char, line_terminator char, enclosure_char and other program variables are loaded from a file.
 *
 * @param int The number of arguments passed
 * @param argv The array of arguements passed to the main function
 * @return int The status of the program returned to the operating system upon termination.
 *
 * @see csv_parser
 *
 * @author Israel Ekpo <israel.ekpo@israelekpo.com>
 */
int main(int argc, char ** argv)
{
	// const char * filename = argv[1];

	/* Declare the variables to be used */
	const char * filename = "example_input.csv";
	const char field_terminator = ',';
	const char line_terminator  = '\n';
	const char enclosure_char   = '"';

	csv_parser file_parser;

	/* Define how many records we're gonna skip. This could be used to skip the column definitions. */
	file_parser.set_skip_lines(1);

	/* Specify the file to parse */
	file_parser.init(filename);

	/* Here we tell the parser how to parse the file */
	file_parser.set_enclosed_char(enclosure_char, ENCLOSURE_OPTIONAL);

	file_parser.set_field_term_char(field_terminator);

	file_parser.set_line_term_char(line_terminator);

	unsigned int row_count = 1U;

	/* Check to see if there are more records, then grab each row one at a time */
	while(file_parser.has_more_rows())
	{
		unsigned int i = 0;

		/* Get the record */
		csv_row row = file_parser.get_row();

		/* Print out each column in the row */
		for (i = 0; i < row.size(); i++)
		{
			printf("COLUMN %02d : %s\n", i + 1U, row[i].c_str());
		}

		printf("====================================================================\n");
		printf("END OF ROW %02d\n", row_count);
		printf("====================================================================\n");

		row_count++;
	}

	return 0;
}