GUI button, string change C#

Hello guys, i’m new to unity forums. I have one problem that you might slove it in one seconds. Sorry for my bad English. -

public string[] Text = new string[] { "Blablabla" };

if(GUI.Button(newRect(100,100,50,50), Text))
{
	// Do action				
}

// Then this Error Come : error CS1502: The best overloaded method match for `UnityEngine.GUI.Button(UnityEngine.Rect, string)’ has some invalid arguments

Why is unity giving me this message ? I hope you guys will help me.

first you have to seperate new from Rect to be like this:

using UnityEngine;
using System.Collections;

public class Button : MonoBehaviour {
	
	
	string text;

	// Use this for initialization
	void Start () {
		
		text = "Hello";
	
	}
	
	// Update is called once per frame
	void Update () {
		
		if(Input.GetKey("space"))
		{
			text = "MyName";
		}
	
	}
	
	void OnGUI()
	{
		GUI.Button (new Rect(100,100, 50, 50), text);
	}
}

Second : Are you sure from the if statement that you want to use it in this way?