WPF web瀏覽器加載HTML與JavaScript

Question

我有這個功能在我的JavaScript函數：

var xhr = new XMLHttpRequest(); 

    var url = 'url'; 
    xhr.open('GET', url, false); 
    xhr.onreadystatechange = function() { 
     if (xhr.readyState == 4) { 
      var str = xhr.responseText; 
      alert(str); 

      var resp = JSON.parse(str); 
      alert('12'); 
      if (0 == resp.ErrorCode) { 
       alert('13'); 
      } 
     } 
    } 
    xhr.send(); 

的STR永遠是：

{"ErrorCode":0,"ErrorMessage":"OK","Command":"/api/getvideoinfo/","data":[{"VideoID":"ehcVomMexkY","IsInCache":true,"IsDownloading":false,"AvailableFormats":[{"DisplayName":"720","IsHD":true,"VidEncMimeType":"video/H264","AudEndMimeType":"audio/aac","Width":1280,"Height":720,"PlaybackURL":"","IsDefaultStream":false},{"DisplayName":"360","IsHD":false,"VidEncMimeType":"video/H264","AudEndMimeType":"audio/aac","Width":640,"Height":360,"PlaybackURL":"url","IsDefaultStream":true}]}]} 

，我注意到，該腳本永遠到不了：

alert('12');

任何想法是什麼會導致這種情況？爲什麼json不會解析？我是否需要將任何庫添加到HTML？

Answer 1

url是服務器上文件的位置。所以url變量應該是從何處得到的數據路徑，在這種情況下，應該是

var url = "/api/getvideoinfo/";