Help returning a variable from this script

Questions & Answers
1

I am trying to make a reusable script which retrieves the text from a url. I cannot figure out a way to return the data variable in DataRetrieved to my other script where I am calling the getData function. I am aware they are using void instead of string right now, I reverted it to how it originally was since I couldn’t figure it out.

The script I am calling:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using System;
using UnityEngine.Networking;

public class GetDatabaseInfo : MonoBehaviour
{
    public void getData(string url)
    {
        StartCoroutine(GetRequest(url,DataRetrieved));     
    }
	private IEnumerator GetRequest(string url,System.Action<string> callback)
		{	
	    	UnityWebRequest request = UnityWebRequest.Get(url);
	    	yield return request.SendWebRequest();
	    	if(request.isNetworkError || request.isHttpError)
	    	{
	    		Debug.LogError(request.error + "  ...Cannot retrieve database information");
	    	}
	    	else
	    	{
	    		callback(request.downloadHandler.text);
	    	}
		}
	private string DataRetrieved(string data)
	{
		Debug.Log(data); //return data variable here
    }
}

The script I am calling it from:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using System;
using UnityEngine.Networking;

public class ValidateRegistration : MonoBehaviour
{
	GetDatabaseInfo getDatabaseInfo;

	private void validate()
	{
		string url = "http://localhost:8080/KingdomRushB_Accounts/Accounts.php";
		getDatabaseInfo=GameObject.FindGameObjectWithTag("DatabaseInfo").GetComponent<GetDatabaseInfo>();  //(allowing me to call the other script's functions from this script)

		string data = getDatabaseInfo.getData(url);
	}

How can I get the data variable to return? I would really appreciate if anyone can help me out

2

Well you’re already getting the data back, you’re just passing it to the wrong function. If you instead pass a callback in the place of DataRetrieved() you can access the data when it’s ready;

public void getData(string url, System.Action<string> callback)
{
    StartCoroutine (GetRequest (url, callback));     
}

private IEnumerator GetRequest(string url,System.Action<string> callback)
{    
    UnityWebRequest request = UnityWebRequest.Get(url);
    yield return request.SendWebRequest();
    if(request.isNetworkError || request.isHttpError)
    {
        Debug.LogError(request.error + "  ...Cannot retrieve database information");
    }
    else
    {
        callback(request.downloadHandler.text);
    }
}

...

private void validate()
{
    string url = "http://localhost:8080/KingdomRushB_Accounts/Accounts.php";
    getDatabaseInfo = GameObject.FindGameObjectWithTag ("DatabaseInfo").GetComponent<GetDatabaseInfo>();  //(allowing me to call the other script's functions from this script)
    getDatabaseInfo.getData(url, onGetData);
}

private void onGetData (string data)
{
    //Use the data here
}

In fact, you don’t even really need a dedicated function; C# has support for anonymous functions in the form of lambdas;

private void validate()
{
    string url = "http://localhost:8080/KingdomRushB_Accounts/Accounts.php";
    getDatabaseInfo = GameObject.FindGameObjectWithTag ("DatabaseInfo").GetComponent<GetDatabaseInfo>();  //(allowing me to call the other script's functions from this script)
    getDatabaseInfo.getData(url, (string data) =>
    {
        //Alternatively, use the data here
    });
}

Just remember that this is asynchronous and so will most likely not happen in the same frame and therefore you cannot depend on the data being immediately available.