AngularJS 如何将返回的图像数据设置为图像的 ng-src

Question

目前我有两个 ASP.Net 核心方法 - 一个与 API 调用相关，另一个与客户端 Razor 助手相关。

它们都位于我的 HomeController.cs。

API:

这是 API 调用：

[HttpGet("api/GetImage")]
public async Task<ActionResult> ImageFromPath()
{
    RestClient client = new RestClient("http://IPADDRESS/cgi-bin/snapshot.cgi?channel=0");
    RestRequest request = new RestRequest(Method.GET);
    request.AddHeader("cache-control", "no-cache");
    request.AddHeader("authorization", "Basic aYu7GI");
    TaskCompletionSource<IRestResponse> taskCompletion = new TaskCompletionSource<IRestResponse>();

    RestRequestAsyncHandle handle = client.ExecuteAsync(request, r => taskCompletion.SetResult(r));
    RestResponse response = (RestResponse)(await taskCompletion.Task);

    return File(response.RawBytes, "image/png");
}

剃须刀：

这是 Razor 助手：

public async Task<ActionResult> ImageFromPath()
{
    RestClient client = new RestClient("http://IPADDRESS/cgi-bin/snapshot.cgi?channel=0");
    RestRequest request = new RestRequest(Method.GET);
    request.AddHeader("cache-control", "no-cache");
    request.AddHeader("authorization", "Basic aYu7GI");
    TaskCompletionSource<IRestResponse> taskCompletion = new TaskCompletionSource<IRestResponse>();

    RestRequestAsyncHandle handle = client.ExecuteAsync(request, r => taskCompletion.SetResult(r));
    RestResponse response = (RestResponse)(await taskCompletion.Task);

    return File(response.RawBytes, "image/png");
}

如您所见，上面的方法体完全相同。一个只有 HttpGet 注释。

然而，当与他们的客户端处理程序配对时，它们会产生不同的结果。

API:

API 调用的客户端处理程序：

<img ng-src="{{imageSrc}}">

$http.get('/api/GetImage', { headers: { 'Accept': 'image/webp,image/apng,image/*,*/*;q=0.8' } }).then(function (response) {
    $scope.imageSrc = response.data;
});

剃须刀：

Razor 助手的客户端处理程序：

<img src="@Url.Action("ImageFromPath")" id="img2" />

结果显示如下：

API:

这是“网络”选项卡中的 API 调用 preview：

剃须刀：

这是网络选项卡中的 Razor Helper 调用 preview：

API:

这是“网络”选项卡中的 API 调用 headers：

剃须刀：

这是网络选项卡中的 Razor Helper 调用 headers：

API:

为什么 Razor 助手实际上是 produce/return 图像，而 API 调用却不是？我怎样才能使 API 调用 return 像 Razor 助手那样的图像？

Answer 1

你需要的东西不多。首先，您不应该直接在 Angular Controller 中访问 DOM。

<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.5.3/angular.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.5.3/angular-animate.js"></script>
<script src="http://angular-ui.github.io/bootstrap/ui-bootstrap-tpls-1.3.2.js"></script>
<div ng-app="app">
    <my-content></my-content>
</div>
<script type="text/javascript">
    angular.module('app', []);

    angular.module('app')
        .component('myContent', {
            template: '<h1>{{$ctrl.title}}</h1><img src="{{$ctrl.imageSrc}}" />',
            controller: function ($http) {
                var self = this;
                self.title = "Title";
                // Just to verify image work
                //self.imageSrc = "https://i.stack.imgur.com/hM8Ah.jpg?s=48&g=1";
                $http.get('/Home/ImageFromPath').then(function (response) {
                    console.log(response.data);
                    self.imageSrc = response.data;
                });
            }
        });
</script>

其次，您需要return base64 编码字符串。

using System;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using RestSharp;

namespace DemoWebCore.Controllers
{
    public class HomeController : Controller
    {
        public async Task<IActionResult> ImageFromPath()
        {
            RestClient client = new RestClient("https://i.stack.imgur.com/hM8Ah.jpg?s=48&g=1");
            RestRequest request = new RestRequest(Method.GET);
            request.AddHeader("cache-control", "no-cache");
            request.AddHeader("authorization", "Basic aYu7GI");
            TaskCompletionSource<IRestResponse> taskCompletion = new TaskCompletionSource<IRestResponse>();
            RestRequestAsyncHandle handle = client.ExecuteAsync(request, r => taskCompletion.SetResult(r));
            RestResponse response = (RestResponse)await taskCompletion.Task;
            return Ok("data:image/png;base64," + Convert.ToBase64String(response.RawBytes));
        }
    }
}

Answer 2

对于此修复，我使用了：

Request.CreateResponse(HttpStatusCode.OK, "data:image/png;base64," + Convert.ToBase64String(response.GetBuffer()))

AngularJS 如何将返回的图像数据设置为图像的 ng-src

How to set returned Image Data as ng-src of image in AngularJS

c#

razor

asp.net-core

rest-client