Unity Shader Toggle KeywordEnum Enum 使用

Shader "Unlit/Custom/Shader05"
{
    Properties
    {
        _MainTex("MainTex",2D) = "white"{}
        [Toggle] _INVERT ("Invert color?", Float) = 0 // _INVERT 必须是大写的 _Invert 不可以 
        [KeywordEnum(None, Add, Multiply)] _Overlay ("Overlay mode", Float) = 0
        [Enum(ON, 0, OFF, 1)] _Enum("Test Enum", float) = 1
    }

    SubShader
    {
        Pass
            {
                CGPROGRAM
                #pragma vertex vert
                #pragma fragment frag
                #include "UnityCG.cginc"
                sampler2D _MainTex;
                #pragma shader_feature _INVERT_ON
                struct AppData
                {
                    float4 position:POSITION;
                    float2 uv:TEXCOORD0;
                };

                struct V2f
                {
                    float4 position:POSITION;
                    float2 uv:TEXCOORD0;
                };

                V2f vert(AppData appdata)
                {
                    V2f o;
                    o.position = UnityObjectToClipPos(appdata.position);
                    o.uv = appdata.uv;
                    return o;
                }

                fixed4 frag(V2f i):SV_Target
                {
                    fixed4 col = tex2D(_MainTex,i.uv);
                    

                    #ifdef _INVERT_ON
                        return fixed4(1,1,0,1);    
                    #else
                        return fixed4(1,0,0,1); 
                    #endif

                }
                ENDCG
            }
    }    
}

        if (Input.GetKeyUp(KeyCode.A))
        {
            //GetComponent<Renderer>().material.SetFloat("_INVERT_ON",1); 这个无效
            GetComponent<Renderer>().material.EnableKeyword("_INVERT_ON");
        }
        
        if (Input.GetKeyUp(KeyCode.D))
        {
            //GetComponent<Renderer>().material.SetFloat("_INVERT_ON",0);
            GetComponent<Renderer>().material.DisableKeyword("_INVERT_ON");
        }