garden_client/Assets/Script/Extension/ExtensionAlpha.cs

using UnityEngine;
using UnityEngine.UI;

using System.Collections;

public static class ExtensionAlpha
{
    public static void SetAlpha(this Graphic graphic, float alpha)
    {
        graphic.color = new Color(graphic.color.r, graphic.color.g, graphic.color.b, alpha);
    }

    public static void SetAlpha(this Material material, string propertyName, float alpha)
    {
        Color color = material.GetColor(propertyName);

        color.a = alpha;

        material.SetColor(propertyName, color);
    }

    public static void SetAlpha(this TextMesh textMesh, float alpha)
    {
        textMesh.color = new Color(textMesh.color.r, textMesh.color.g, textMesh.color.b, alpha);
    }

    public static void SetAlpha(this SpriteRenderer sR, float alpha)
    {
        sR.color = new Color(sR.color.r, sR.color.g, sR.color.b, alpha);
    }


    public static float GetAlpha(this Material material, string propertyName)
    {
        Color color = material.GetColor(propertyName);

        return color.a;
    }
}