[c#] How can I let something happen after a small delay?

Questions & Answers
1

How can I add a small delay between things happening in a function, after the delay it should continue with what it was doing? in C#

4

you can Invoke a method after a delay like this

 Invoke("DoSomething", 2);//this will happen after 2 seconds
2

You can do it with coroutines in any MonoBehaviour:

IEnumerator ExecuteAfterTime(float time)
{
    yield return new WaitForSeconds(time);

    // Code to execute after the delay
}

You can call it with, for example, StartCoroutine(ExecuteAfterTime(10));

Note that it will execute asynchronous so put everything that has to wait for it to be done, inside the coroutine.

5

We can extend this futher by executing an Action after the delay:

IEnumerator ExecuteAfterTime(float time, Action task)
{
    if (isCoroutineExecuting)
        yield break;

    isCoroutineExecuting = true;

    yield return new WaitForSeconds(time);

    task();

    isCoroutineExecuting = false;
}

Then use it like this:

 StartCoroutine(ExecuteAfterTime(0.5f, () =>
    {            
        //Add somwthing here
    }));
6

use this class :

using System.Collections;
using System.Collections.Generic;
using System.Reflection;
using System.Linq;
using UnityEngine;
using System;

namespace LateExe {
    class Executer
    {
        object script;
        MonoBehaviour mono_script;
        public Executer(object script)
        {
            this.script = script;
            this.mono_script = this.script as MonoBehaviour;
        }
        public InvokeId DelayExecute(float DelayInSeconds, Action<object[]> lambda, params object[] parameters)
        {

           return new InvokeId( mono_script.StartCoroutine(Delayed(DelayInSeconds, lambda, parameters)));
        }
        public InvokeId DelayExecute(float DelayInSeconds, string methodName, params object[] parameters)
        {
            foreach (MethodInfo method in script.GetType().GetMethods())
            {
                if (method.Name == methodName)
                    return new InvokeId(mono_script.StartCoroutine(Delayed(DelayInSeconds, method, parameters)));
            }
            return null;
        }
        public InvokeId ConditionExecute(Func<bool> condition, string methodName, params object[] parameters)
        {
            foreach (MethodInfo method in script.GetType().GetMethods())
            {
                if (method.Name == methodName)
                    return new InvokeId(mono_script.StartCoroutine(Delayed(condition, method, parameters)));
            }
            return null;
        }
        public InvokeId ConditionExecute(Func<bool> condition, Action<object[]> lambda, params object[] parameters)
        {
            return new InvokeId(mono_script.StartCoroutine(Delayed(condition, lambda, parameters)));
        }

        public void StopExecute(InvokeId id)
        {
            mono_script.StopCoroutine(id.coroutine);
        }
        IEnumerator Delayed(float DelayInSeconds, Action<object[]> lambda, params object[] parameters)
        {
            yield return new WaitForSeconds(DelayInSeconds);
            lambda.Invoke(parameters);
        }
        IEnumerator Delayed(float DelayInSeconds, MethodInfo method, params object[] parameters)
        {
            yield return new WaitForSeconds(DelayInSeconds);
            method.Invoke(script, parameters);
        }
        IEnumerator Delayed(Func<bool> condition, Action<object[]> lambda, params object[] parameters)
        {
            yield return new WaitUntil(condition);
            lambda.Invoke(parameters);
        }
        IEnumerator Delayed(Func<bool> condition, MethodInfo method, params object[] parameters)
        {
            yield return new WaitUntil(condition);
            method.Invoke(script, parameters);
            
        }

    }
    class InvokeId
    {
        public readonly Coroutine coroutine;
        public InvokeId(Coroutine coroutine)
        {
            this.coroutine = coroutine;
        }
    }
}

Examples:
execute after 2 seconds in a few ways

using LateExe;

public class Game_Script: MonoBehaviour {
void Awake {
Executer exe = new Executer(this);
exe.DelayExecute(2f , x=> Debug.Log("after 2 seconds"));
exe.DelayExecute(2f , x=> Debug.log(x[0]) , "after 2 seconds + params");
exe.DelayExecute(2f , "after2seconds");
exe.DelayExecute(2f , "afterXseconds", 2);
exe.DelayExecute(2f , "afterXY", 2, " seconds");
}
void after2seconds ()
{
Debug.Log("after 2 seconds");
}
void afterXseconds(int x) {
Debug.log("after" + x + "seconds");
}
void afterXY(int x , string y) {
Debug.log("after " + x + y);
}
}

Example stop:

 var id = exe.DelayExecute(0.5f, x => Debug.Log("not gonna run"));
        exe.StopExecute(id);

Example when:

exe.ConditionExecute(() => score > 100 , x => Debug.Log("you're good"));

I know this is old but its a very common thing and I hope unity will one day implement such a class into the engine. creating a coroutine every time is not a clean way of doing things.

3

Check Coroutines.

It is exactly what you need.

7

If all other comments don’t help you, then use this. Maybe it’s not good to write like that…But I don’t care :slight_smile:

void AddSomePassive()
    {
        counter++;
        if (counter == 10)
        {
            ItemsUpdate();
            count = count + dps;
            counttmp = count;
        }
        else if (counter > 10) counter = 0;
    }
8

Check this. That was a clue for me :smiley: