Version: 2018.2
public string text ;

Description

The current value of the input field.

Note that null is invalid value for InputField.text.

using UnityEngine;
using System.Collections;
using UnityEngine.UI; // Required when Using UI elements.

public class Example : MonoBehaviour { public InputField mainInputField;

public void Start() { mainInputField.text = "Enter Text Here..."; } }