Read specific column in CSV to Array - php

Question

I am trying to read a certain data in my csv file and transfer it to an array. What I want is to get all the data of a certain column but I want to start on a certain row (let say for example, row 5), is there a possible way to do it? What I have now only gets all the data in a specific column, want to start it in row 5 but can't think any way to do it. Hope you guys can help me out. Thanks!
<?php
//this is column C
$col = 2;
// open file
$file = fopen("example.csv","r");
while(! feof($file))
{
echo fgetcsv($file)[$col];
}
// close connection
fclose($file);
?>

Answer 1

Yes you can define some flag to count the row. Have a look on below solution. It will start printing from 5th row, also you can accesscolum by its index. For eg. for second column you can use $row[1]
$start_row = 5; //define start row
$i = 1; //define row count flag
$file = fopen("myfile.csv", "r");
while (($row = fgetcsv($file)) !== FALSE) {
if($i >= $start_row) {
print_r($row);
//do your stuff
}
$i++;
}
// close file
fclose($file);

Answer 2

You have no guarantee that your file exists or you can read it or ....
Similar to fgets() except that fgetcsv() parses the line it reads for fields in CSV format and returns an array containing the fields read. PHP Manual
//this is column C
$col = 2;
// open file
$file = fopen("example.csv","r");
if (!$file) {
// log your error ....
}
else {
while( ($row = fgetcsv($file)) !== FALSE){
if (isset($row[$col])) // field doesn't exist ...
else print_r ($row[$col]);
}
}
// close file
fclose($file);
?>

Answer 3

Depending on the quality and volume of your incoming data, you may wish to use iterated conditions to build your output array or you may prefer to dump all of the csv data into a master array and then filter it to the desired structure.
To clarify the numeracy in my snippets, the 5th row of data with be located at index [4]. The same indexing is used for column targeting -- the 4th column is at index [3].
A functional approach (assumes no newlines in values and is not set up with any extra csv parsing flags):
$starting_index = 4;
$target_column = 3;
var_export(
array_column(
array_slice(
array_map(
'str_getcsv',
file('example.csv')
),
$starting_index
),
$target_column
)
);
A language construct approach with leading row exclusions based on a decrementing counter.
$disregard_rows = 4;
$target_column = 3;
$file = fopen("example.csv", "r");
while (($row = fgetcsv($file)) !== false) {
if ($disregard_rows) {
--$disregard_rows;
} else {
$column_data[] = $row[$target_column];
}
}
var_export($column_data);