Info Box Attribute

[Title("InfoBox message types")]
[InfoBox("Default info box.")]
public int A;

[InfoBox("Warning info box.", InfoMessageType.Warning)]
public int B;

[InfoBox("Error info box.", InfoMessageType.Error)]
public int C;

[InfoBox("Info box without an icon.", InfoMessageType.None)]
public int D;

[Title("Conditional info boxes")]
public bool ToggleInfoBoxes;

[InfoBox("This info box is only shown while in editor mode.", InfoMessageType.Error, "IsInEditMode")]
public float G;

[InfoBox("This info box is hideable by a static field.", "ToggleInfoBoxes")]
public float E;

[InfoBox("This info box is hideable by a static field.", "ToggleInfoBoxes")]
public float F;

[Title("Info box member reference and attribute expressions")]
[InfoBox("$InfoBoxMessage")]
[InfoBox("@\"Time: \" + DateTime.Now.ToString(\"HH:mm:ss\")")]
public string InfoBoxMessage = "My dynamic info box message";

private static bool IsInEditMode()
{
    return !Application.isPlaying;
}