GUISkin.textField

public GUIStyle textField ;

설명

Style used by default for GUI.TextField controls.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    public GUIStyle style;
    private string str = "A string...";
    void OnGUI() {
        GUI.skin.textField = style;
        str = GUILayout.TextField(str);
    }
}