Version: 2018.1
public ParticleSystem.MinMaxCurve startLifetime ;


The total lifetime in seconds that each new particle will have.

This value is set on the particle when it is created by the particle system. Assign a value of float.PositiveInfinity to particles to prevent the Particle System from destroying them. This gives the particles an infinite lifespan. See Also: MinMaxCurve.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { private ParticleSystem ps; public float hSliderValue = 1.0F;

void Start() { ps = GetComponent<ParticleSystem>(); }

void Update() { var main = ps.main; main.startLifetime = hSliderValue; }

void OnGUI() { hSliderValue = GUI.HorizontalSlider(new Rect(25, 45, 100, 30), hSliderValue, 0.0F, 5.0F); } }