The input is sanitized by parsing the HTML into tokens. All safe tokens (from a whitelist) are
  then serialized back to properly escaped html string. This means that no unsafe input can make
  it into the returned string, however, since our parser is more strict than a typical browser
  parser, it's possible that some obscure input, which would be recognized as valid HTML by a
  browser, won't make it through the sanitizer. The input may also contain SVG markup.
  The whitelist is configured using the functions aHrefSanitizationWhitelist and
  imgSrcSanitizationWhitelist of $compileProvider.
$sanitize(html);
| Param | Type | Details | 
|---|---|---|
| html | string | HTML input. | 
| string | Sanitized HTML. | 
     <script>
         angular.module('sanitizeExample', ['ngSanitize'])
           .controller('ExampleController', ['$scope', '$sce', function($scope, $sce) {
             $scope.snippet =
               '<p style="color:blue">an html\n' +
               '<em onmouseover="this.textContent=\'PWN3D!\'">click here</em>\n' +
               'snippet</p>';
             $scope.deliberatelyTrustDangerousSnippet = function() {
               return $sce.trustAsHtml($scope.snippet);
             };
           }]);
     </script>
     <div ng-controller="ExampleController">
        Snippet: <textarea ng-model="snippet" cols="60" rows="3"></textarea>
       <table>
         <tr>
           <td>Directive</td>
           <td>How</td>
           <td>Source</td>
           <td>Rendered</td>
         </tr>
         <tr id="bind-html-with-sanitize">
           <td>ng-bind-html</td>
           <td>Automatically uses $sanitize</td>
           <td><pre><div ng-bind-html="snippet"><br/></div></pre></td>
           <td><div ng-bind-html="snippet"></div></td>
         </tr>
         <tr id="bind-html-with-trust">
           <td>ng-bind-html</td>
           <td>Bypass $sanitize by explicitly trusting the dangerous value</td>
           <td>
           <pre><div ng-bind-html="deliberatelyTrustDangerousSnippet()">
</div></pre>
           </td>
           <td><div ng-bind-html="deliberatelyTrustDangerousSnippet()"></div></td>
         </tr>
         <tr id="bind-default">
           <td>ng-bind</td>
           <td>Automatically escapes</td>
           <td><pre><div ng-bind="snippet"><br/></div></pre></td>
           <td><div ng-bind="snippet"></div></td>
         </tr>
       </table>
       </div>it('should sanitize the html snippet by default', function() {
  expect(element(by.css('#bind-html-with-sanitize div')).getInnerHtml()).
    toBe('<p>an html\n<em>click here</em>\nsnippet</p>');
});
it('should inline raw snippet if bound to a trusted value', function() {
  expect(element(by.css('#bind-html-with-trust div')).getInnerHtml()).
    toBe("<p style=\"color:blue\">an html\n" +
         "<em onmouseover=\"this.textContent='PWN3D!'\">click here</em>\n" +
         "snippet</p>");
});
it('should escape snippet without any filter', function() {
  expect(element(by.css('#bind-default div')).getInnerHtml()).
    toBe("<p style=\"color:blue\">an html\n" +
         "<em onmouseover=\"this.textContent='PWN3D!'\">click here</em>\n" +
         "snippet</p>");
});
it('should update', function() {
  element(by.model('snippet')).clear();
  element(by.model('snippet')).sendKeys('new <b onclick="alert(1)">text</b>');
  expect(element(by.css('#bind-html-with-sanitize div')).getInnerHtml()).
    toBe('new <b>text</b>');
  expect(element(by.css('#bind-html-with-trust div')).getInnerHtml()).toBe(
    'new <b onclick="alert(1)">text</b>');
  expect(element(by.css('#bind-default div')).getInnerHtml()).toBe(
    "new <b onclick=\"alert(1)\">text</b>");
});