Question

I need to send SMS to the user, before send the message I want remove the unsupported characters from the message. I added my API documentation lines as the reference.

Generally speaking, only a subset of the standard ASCII character set is supported for content being delivered to the user via SMS. The list of supported characters are A-Z, a-z, 0-9 and the following:

@$_/.,"():;-=+*&%#!?<>' plus space and newline "\n".

Most special characters are not supported and will cause messages to be rejected by the wireless operators. In particular, accented characters and the following are NOT supported:

tab [ ] ~ { } ^ | € \

When authoring content for delivery via SMS, it is also important to use the simple ASCII characters for the apostrophe, the ellipsis, and single and double quotes:

use ' instead of <`> and <’>

use " instead of <“> and <”>

use ... instead of … (Note: that’s three separate periods instead of the single ellipsis character)

So I’m looking for regular expression to satisfy this requirement.

Answer 1

You could replace all characters that don’t match the valid ones:

[^A-Za-z0-9@$_\/.,"():;\-=+&%#!?<>' \n]

The [] means: “any of” and the ^ means: “not”. So the whole expression says: Match anything but…

So you’d write:

replace all [^A-Za-z0-9@$_\/.,"():;\-=+&%#!?<>' \n] in the SMS by nothing

For further information (and your further questions ;-)) please have a look at this Howto.