问如何在JavaScript中删除blob文件？

EN

        public view_image(_tImagen: iConfigImagen){
        var img_view = this.prop_div_vizualizador;

        var _window: any = window;
            var xhr = new XMLHttpRequest();
            xhr.open("GET", _tImagen.url, true);
            xhr.responseType = "blob";
            xhr.onload = function () {
                var urlCreator = _window.URL = _window.URL || _window.webkitURL;
                var imageUrl = urlCreator.createObjectURL(this.response);
                _tImagen.urlBlob = imageUrl;
                img_view.style("background-image", "url(" + _tImagen.urlBlob + ")");
            }
    }