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is there a function in PHP that I can use to replace a specific character with another one, but I should be able to limit the number of replacements done? I am currently trying to get preg_replace() to work, as it has that ability, but there seems to be something wrong. Here is what I am using:

$args[0] = preg_replace("/\$/", $args[$x], $args[0], 1);

$args[0] contains letters and special "$" characters, which should be replaced.

Any help?

Have you tried "/\\$/" (2 backslashes)?

(See How to escape $ in PHP using preg_replace? for more info)

This is the syntax of replacement fn:

preg_replace($patterns, $replacements, $string);

so you have to put first the patterns after that the replacements (the char you want to replace with it) at the end of your string.