我在StackExchange上读了很多帖子，但找不到我需要的确切内容。注意：这不仅仅是为了删除重复项。我需要浏览File1.csv并创建一个新文件-Results.csv，其中包含的每一行都不包含File2.txt中的一行。
File1.csv包含个人详细信息和电子邮件地址，每行1个：
"mr","Happy","Man","mrhappy@example.com"
"mr","Sad","Man","mrsad@example.com"
"mr","Grumpy","Man","mrgrumpy@example.com"
"mr","Strong","Man","mrstrong@example.com"
File2.txt包含电子邮件地址，每行1个：
mrhappy@example.com
mrsomeoneelse@example.com
mrsomeoneelse2@example.com
预期结果：Results.csv应包含：
"mr","Sad","Man","mrsad@example.com"
"mr","Grumpy","Man","mrgrumpy@example.com"
"mr","Strong","Man","mrstrong@example.com"
令人困惑的是，当File2.txt包含一行时，我的代码可以正常工作。但当它包含多行时，Results.txt包含File1.csv中的所有行（包括应该删除的行），并多次重复这些行（与File2.txt中的行一样多）。
我的代码：
<?php
$to_be_searched = "File1.csv";
$items_to_catch = file("File2.txt");
// create empty array to store lines we want to keep - i.e. lines that dont contain emails we're checking for
$good_lines = array();
// open $to_be_searched
$handle = fopen($to_be_searched, "r");
if ($handle) {
// go line by line until end of file
while (($line = fgets($handle)) !== false) {
// check if line contains any items from $items_to_catch
foreach($items_to_catch as $key => $value) {
if(strpos($line, $value) === false) {
// email wasn't found on the line so we want this line in the results file, therefore add to $good_lines array
$good_lines[] = $line;
}
}
}
fclose($handle);
} else {
echo "Couldn't open " . $to_be_searched;
exit();
}
// write $array_of_good_lines into new file
$new_file = "Results.csv";
foreach($good_lines as $key => $value) {
file_put_contents($new_file, $value, FILE_APPEND | LOCK_EX);
}
?>
我做错了什么？
它目前不起作用，因为在foreach中，您将多次向$good_lines添加同一行。
要解决此问题，可以在循环中添加一个标志变量。
while (($line = fgets($handle)) !== false) {
// Declare our flag variable as false by default
$found = false;
// Loop through each item to see if the email has been found
foreach($items_to_catch as $key => $value) {
// If the email was found, stop looping in the second file
if(strpos($line, $value) !== false){
$found = true;
break;
}
}
// If the email was not found in the second file, add it to the good_lines array
if(!$found)
$good_lines[] = $line;
}
更新
除了循环之外，在读取File2.txt时还有另一个问题，因为它将换行符添加到字符串中，因此，当稍后将字符串与strpos进行比较时，它不起作用。解决方法：
$items_to_catch = file("File2.txt", FILE_IGNORE_NEW_LINES);
这是$items_to_catch的var_dump，不带标志：
array (size=3)
0 => string 'mrhappy@example.com
' (length=20)
1 => string 'mrsomeoneelse@example.com
' (length=26)
2 => string 'mrsomeoneelse2@example.com
' (length=27)
这是$items_to_catch的var_dump，其标志为：
array (size=3)
0 => string 'mrhappy@example.com' (length=19)
1 => string 'mrsomeoneelse@example.com' (length=25)
2 => string 'mrsomeoneelse2@example.com' (length=26)
请注意每个电子邮件中的额外字符，即换行符。
file()返回文件的每一行，包括结束的终端行。如果你使用Symfony的VarDumper组件查看$items_to_catch，你会发现它看起来像：
array:3 [
0 => "mrhappy@example.com'n"
1 => "mrsomeoneelse@example.com'n"
2 => "mrsomeoneelse2@example.com'n"
]
这不是您想要的，因为您稍后的比较不包括终点线结束。顺便说一句，Symfony的VarDumper组件比print_r和var_dump好几个数量级：我强烈建议将其组合到您的项目中。
因此，用修剪掉新的终端线路
$items_to_catch = array_map('trim', file('File2.txt'));
一个最小的工作示例：
$excludedLinesWithTheseEmails = array_map('trim', file('File2.txt'));
$out = fopen('Results.csv', 'w') or die('Cannot open Results.csv');
$in = fopen('File1.csv', 'r') or die('Cannot open File1.csv');
while (false !== ($row = fgetcsv($in))) {
if (! in_array($row[3], $excludedLinesWithTheseEmails)) {
fputcsv($out, $row);
}
}
fclose($out);
fclose($in);