$http({  
        method: "DELETE",headers: {'Content-Type': 'application/json',Authorization: "Bearer " + rootServices.getToken() }  
    })

或者您可以将其设置为广泛的：

module.config(function($httpProvider) {
  //$http.defaults.headers.common.Authorization = 'Basic YmVlcDpib29w'
  $httpProvider.defaults.headers.delete = { 'Content-Type' : 'application/json' };
});

文档状态：

Setting HTTP Headers The $http service will automatically add certain
HTTP headers to all requests. These defaults can be fully configured
by accessing the $httpProvider.defaults.headers configuration object,
which currently contains this default configuration:

$httpProvider.defaults.headers.common (headers that are common for all
requests): Accept: application/json,* / *
$httpProvider.defaults.headers.post: (header defaults for POST
requests) Content-Type: application/json
$httpProvider.defaults.headers.put (header defaults for PUT requests)
Content-Type: application/json To add or overwrite these defaults,
simply add or remove a property from these configuration objects. To
add headers for an HTTP method other than POST or PUT,simply add a
new object with the lowercased HTTP method name as the key,e.g.
`$httpProvider.defaults.headers.get = { ‘My-Header’ : ‘value’ }.

The defaults can also be set at runtime via the $http.defaults object
in the same fashion. For example:

https://docs.angularjs.org/api/ng/service/$http