i use my.enable_impact for my weapon.but when i jump on it,the function doesnt start.what should i do?

You should use either enable_entity or c_trace to detect another object jumping on it. In your event function, script
Code:

---

  

if(event_entity == 1)
{
weaponfunction();
}

---

Impaler is right, kind of.
Best is to use both enable_impact and enable_entity:
Code:

---

if(event_type == event_impact || event_type == event_entity)
{
  //do your stuff here
}

---

However if you already use a c_trace in the player's movement action (for gravity), then you could set the c_trace flag 'ACTIVATE_SONAR' and use the event_sonar to detect the player.
But this will also pick up the weapon if the player just jumps over it, so you may use the mentioned event_entity and event_impact.

thanks!