Remove Blank ROWS from CSV files in php

问题:

Is it possible to remove all blank ROWS from a CSV file?

I'm trying to count all rows from a CSV file but would like to exclude lines that doesn't contain a value on a specific column or the whole row.

This is what I'm using to count the rows as of the moment.

$import = file($target_path, FILE_SKIP_EMPTY_LINES);
$num_rows = count($import);
echo $num_rows;

sample:

Jun,Bronse,137 Raven,Princeton,TX,75407,2147088671,[e-mail],1990,CHEVROLET,K1500,,
,,,,,,,,,,,,
,,,,,,,,,,,,
,,,,,,,,,,,,
Nella,Brown,111 Venna St,Princeton,TX,75407,2147177671,[e-mail],1993,CHEVROLET,K1500,,
Jun,Bronse,137 Raven,Princeton,TX,75407,2147088671,[e-mail],1990,CHEVROLET,K1500,,
,,,,,,,,,,,,
Jun,Bronse,137 Raven,Princeton,TX,75407,2147088671,[e-mail],1990,CHEVROLET,K1500,,

回答1:

$lines = file("test.csv", FILE_SKIP_EMPTY_LINES | FILE_IGNORE_NEW_LINES);
$num_rows = count($lines);
foreach ($lines as $line) {
    $csv = str_getcsv($line);
    if (empty($csv[SPECIFIC_COLUMN])) {
        $num_rows--;
    }
}

If you don't want to check a specific column, but just filter out rows where all columns are empty, change it to:

    if (count(array_filter($csv)) == 0) {

回答2:

For empty rows:

$lines = file("test.csv", FILE_SKIP_EMPTY_LINES | FILE_IGNORE_NEW_LINES);
$num_rows = count($lines);
foreach ($lines as $line) {
    $csv = str_getcsv($line);
    if (!array_filter($csv)) {
        $num_rows--;
    }
}

回答3:

$filename = "test.csv";

if (($fp = fopen($filename, "r")) !== FALSE) { 
    $rows = explode("\n", $fp);
    $csv = "";

    foreach($rows as $r) {
        if(str_replace(array(" ", ","), "", $r) != "")
            $csv .= $r."\n";
    }

    file_put_contents($filename, $csv);;
}

回答4:

Basically what Barmar already posted, but if you need to process (many) large* files, I'd recommend to give rtrim (or ltrim) a try, since usually those are a bit faster for a task like yours:

$lines = file("test.csv", FILE_SKIP_EMPTY_LINES | FILE_IGNORE_NEW_LINES);
$num_rows = count($lines);
foreach ($lines as $line) {
    if (!rtrim($line, ',')) {
        $num_rows--;
    }
}

---

*_{By large I mean that large that it's really worth it. Don't waste your time doing micro-optimizations.}

回答5:

use notepad++ to open .csv file. Then search for ^\*s goto find and replace and click replace all button. This should solve your problem.