问题
I am really new to php and everything I have learned is from my school textbook and online research. With that said I am trying to complete an assignment and I am stuck on the last part. for the final part the assignment says to "Create a PHP script that will dump the contents of the employee table into CSV text file that has comma separated values for each record. Each new record should begin on a new line". I have tried many online tutorials but none of them teach how to put this event in a button. I am including my code so you can see the mess I have. It's not to bad but I am sure I can do the same task with much less code. Again I am just starting out and this is the best I can do for now. Could anyone give any suggestions on how this could be done. I have my button on line 140. I also used a db_connect() function so i don't have to write it many times. I can peon use this to read the database before I save as a csv.
Any suggestions would be greatly appreciated. Be warned It's a lot of code to follow.
<h2>Employee Search</h2>
<form action="Draft.php" name="dbToCSV" method="GET">
<input type="submit" name="dbToCSV" value="Export Database to CSV" <?php if (isset($_GET['dbToCSV']))
{
//Do this code
}
else
{
echo "Error!";
} ?>><br />
</form>
<form action="Draft.php" method="GET">
By name: <input type="text" name="searchName">
<input type="submit" value="Search Name"><br />
</form>
<form action="Draft.php" method="GET">
By language: <input type="text" name="searchLang">
<input type="submit" value="Search Language"><br />
</form>
回答1:
It's 2017 and mysqli is more common than mysql now. So here's a mysqli version of Josh Liptzin's answer:
<?php
/* Attempt MySQL server connection. */
$connection = mysqli_connect($database_server, $database_username, $database_password, $database_name);
// Check connection
if($connection === false){
die("ERROR: Could not connect. " . mysqli_connect_error());
}
$query = "SELECT * FROM Employee_data";
$result = mysqli_query($connection, $query);
$number_of_fields = mysqli_num_fields($result);
$headers = array();
for ($i = 0; $i < $number_of_fields; $i++) {
$headers[] = mysqli_field_name($result , $i);
}
$fp = fopen('php://output', 'w');
if ($fp && $result) {
header('Content-Type: text/csv');
header('Content-Disposition: attachment; filename="export.csv"');
header('Pragma: no-cache');
header('Expires: 0');
fputcsv($fp, $headers);
while ($row = $result->fetch_array(MYSQLI_NUM)) {
fputcsv($fp, array_values($row));
}
die;
}
function mysqli_field_name($result, $field_offset)
{
$properties = mysqli_fetch_field_direct($result, $field_offset);
return is_object($properties) ? $properties->name : null;
}
?>
回答2:
You are literally trying to put the PHP code inside the HTML button. The button can simply be a link to another page (like dump.php), which contains some PHP like the following:
Link:
<a href="dump.php" target="_blank">Download employee data</a>
dump.php:
<?php
$result = mysql_query('SELECT * FROM `employee_data`');
if (!$result) die('Couldn\'t fetch records');
$num_fields = mysql_num_fields($result);
$headers = array();
for ($i = 0; $i < $num_fields; $i++) {
$headers[] = mysql_field_name($result , $i);
}
$fp = fopen('php://output', 'w');
if ($fp && $result) {
header('Content-Type: text/csv');
header('Content-Disposition: attachment; filename="export.csv"');
header('Pragma: no-cache');
header('Expires: 0');
fputcsv($fp, $headers);
while ($row = $result->fetch_array(MYSQLI_NUM)) {
fputcsv($fp, array_values($row));
}
die;
}
?>
Code source: PHP code to convert a MySQL query to CSV
For your own sake you shouldn't copy and paste the above code into your assignment - there's a world of difference between the code you posted and the code above that the grader will instantly pick up on.
回答3:
So the class is over and I figure I would show how I resolved my issue. this made the most sense to me and it didn't take many lines of code. I am sure there are possibly even shorter ways to do this but for being very new to php i thing I did an ok job with the code.
I basically made an if statement that checks if there are any records in the database then it takes each record field and writes it to the cdv file while adding a comma. I did this code twice. The top code writes the database field names and the second half writes the values in those fields. Thanks for the advice everyone. I am glad I was able to figure it out in time to submit my assignment.
if (isset($_GET['dbToCSV']))
{
// database connection
db_connect();
$query = mysql_query("SELECT * FROM employee_data") or die(mysql_error());
$number_rows = mysql_num_rows($query);
if ($number_rows >= 1)
{
$filename = "exported_db_" . date("m-d-Y_hia") . ".csv"; // filenme with date appended
$fp = fopen($filename, "w"); // open file
$row = mysql_fetch_assoc($query);
$seperator = "";
$comma = "";
foreach ($row as $name => $value)
{
$seperator .= $comma . $name; // write first value without a comma
$comma = ","; // add comma in front of each following value
}
$seperator .= "\n";
echo "Database has been exported to $filename";
fputs($fp, $seperator);
mysql_data_seek($query, 0); // use previous query leaving out first row
while($row = mysql_fetch_assoc($query))
{
$seperator = "";
$comma = "";
foreach ($row as $name => $value)
{
$seperator .= $comma . $value; // write first value without a comma
$comma = ","; // add comma in front of each following value
}
$seperator .= "\n";
fputs($fp, $seperator);
}
fclose($fp);
}
else
echo "There are no records in the database to export.";
mysql_close();
}
回答4:
Following is PHP script which I am using.
<?php
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
die('Could not connect: ' . mysql_error());
}
$table_name = "employees";
$fp = fopen('php://output', 'w');
header('Content-Type: text/csv');
header('Content-Disposition: attachment; filename="'.$table_name.'.csv"');
header('Pragma: no-cache');
header('Expires: 0');
$result = mysql_query("SELECT * FROM $table_name");
if (!$result) die("Couldn't fetch records");
$num_fields = mysql_num_fields($result);
$headers = array();
for ($i = 0; $i < $num_fields; $i++) {
$headers[] = mysql_field_name($result , $i);
}
if ($fp && $result) {
fputcsv($fp, $headers);
while ($row = mysql_fetch_assoc($result)) {
fputcsv($fp, $row);
}
}
exit;
?>
来源：https://stackoverflow.com/questions/21923934/exporting-table-to-csv-via-php-button