How do you change setting using strings?

In a map I'm making I have diffrent camera settings for every player. What I want to know is how do you change the distance of the players current camera by using strings.

Example

Player enters-- Cam Distance (then a number)

Then the distance of the current cammera changes to the integer substring after Cam Distance.

I've seen this done in the DM_MOD maps, but how was it accomplished?

Thanks