如何在PHP中将多个数字连接在一起作为字符串？

Question

I need to create a comma separated string of numbers.

The issue I'm running into is that, in the end, I'm getting a total of all the numbers when it should be like:

2, 10, 35, 56, 67', etc.

Here's what I'm doing:

$field_ids = '';

// begin while loop
<?php $field_ids = bp_get_the_profile_field_ids(); ?>
// end while loop

// begin while loop
<?php $field_ids += bp_get_the_profile_field_ids(); ?>
// end while loop

<input type="hidden" name="field_ids" id="field_ids" value="<?php echo $field_ids; ?>">

How can I get this:

<input type="hidden" name="field_ids" id="field_ids" value="2, 10, 35, 56, 67">

instead of this:

<input type="hidden" name="field_ids" id="field_ids" value="170">

Answer 1

Yes you could gather them as an array, then use implode() to do this:

$field_ids = array(); // initialize as array

while(...) { // begin while loop block
    $field_ids[] = bp_get_the_profile_field_ids(); // push it inside
} // end while loop block

$field_ids = implode(', ', $field_ids); // implode/glue those ids by comma

<input type="hidden" name="field_ids" id="field_ids" value="<?php echo $field_ids; ?>">

By using += you're continually adding them up until the end of the loop resulting to its summation.