[Sledgehammer]

Put the code under the function: 'OnPlayerKeyStateChange(playerid, newkeys, oldkeys)'.

You got to define what key you want. https://sampwiki.blast.hk/wiki/Keys

I.e

pawn Код:

public OnPlayerKeyStateChange(playerid, newkeys, oldkeys)
{
if(IsKeyJustDown(KEY_CROUCH, newkeys, oldkeys))
{
//Your code here. 
}
return 1;
}