使用jquery ajax下載pdf文件

Question

我想爲jquery ajax響應下載pdf文件。 Ajax響應包含pdf文件數據。我試過這個solution。我的代碼如下，但我總是得到一個空白的PDF。

$(document).on('click', '.download-ss-btn', function() { 

    $.ajax({ 
     type: "POST", 
     url: 'http://127.0.0.1:8080/utils/json/pdfGen', 
     data: { 
      data: JSON.stringify(jsonData) 
     } 

    }).done(function (data) { 
     var blob = new Blob([data]); 
     var link = document.createElement('a'); 
     link.href = window.URL.createObjectURL(blob); 
     link.download = "Sample.pdf"; 
     link.click(); 
    }); 


}); 

Answer 1

jQuery有一些問題，使用AJAX請求，因爲它還沒有實現一些HTML5 XHR V2功能加載的二進制數據，請參閱本enhancement request這discussion

鑑於這種情況，有兩種解決方法之一：

首先解決方案，放棄jQuery和使用XMLHttpRequest

圍棋與本地HTMLHTTPRequest，這裏是代碼做你需要

var req = new XMLHttpRequest(); 
    req.open("GET", "/file.pdf", true); 
    req.responseType = "blob"; 

    req.onload = function (event) { 
    var blob = req.response; 
    console.log(blob.size); 
    var link=document.createElement('a'); 
    link.href=window.URL.createObjectURL(blob); 
    link.download="Dossier_" + new Date() + ".pdf"; 
    link.click(); 
    }; 

    req.send(); 

二的解決方案，使用jQuery的AJAX本地插件

該插件可以發現here，可用於對XHR V2能力，JQuery的缺失，這裏是一個示例代碼如何使用它

$.ajax({ 
    dataType: 'native', 
    url: "/file.pdf", 
    xhrFields: { 
    responseType: 'blob' 
    }, 
    success: function(blob){ 
    console.log(blob.size); 
     var link=document.createElement('a'); 
     link.href=window.URL.createObjectURL(blob); 
     link.download="Dossier_" + new Date() + ".pdf"; 
     link.click(); 
    } 
}); 

Answer 2

我是新手，大多數的代碼是從谷歌搜索。我得到了我的pdf下載與下面的代碼（試錯遊戲）。感謝上面的代碼提示（xhrFields）。

$.ajax({ 
      cache: false, 
      type: 'POST', 
      url: 'yourURL' 
      contentType: false, 
      processData: false, 
      data: yourdata, 
      //xhrFields is what did the trick to read the blob to pdf 
      xhrFields: { 
       responseType: 'blob' 
      }, 
      success: function (response, status, xhr) { 

       var filename = "";     
       var disposition = xhr.getResponseHeader('Content-Disposition'); 

       if (disposition) { 
        var filenameRegex = /filename[^;=\n]*=((['"]).*?\2|[^;\n]*)/; 
        var matches = filenameRegex.exec(disposition); 
        if (matches !== null && matches[1]) filename = matches[1].replace(/['"]/g, ''); 
       } 
       var linkelem = document.createElement('a'); 
       try { 
              var blob = new Blob([response], { type: 'application/octet-stream' });       

        if (typeof window.navigator.msSaveBlob !== 'undefined') { 
         // IE workaround for "HTML7007: One or more blob URLs were revoked by closing the blob for which they were created. These URLs will no longer resolve as the data backing the URL has been freed." 
         window.navigator.msSaveBlob(blob, filename); 
        } else { 
         var URL = window.URL || window.webkitURL; 
         var downloadUrl = URL.createObjectURL(blob); 

         if (filename) { 
          // use HTML5 a[download] attribute to specify filename 
          var a = document.createElement("a"); 

          // safari doesn't support this yet 
          if (typeof a.download === 'undefined') { 
           window.location = downloadUrl; 
          } else { 
           a.href = downloadUrl; 
           a.download = filename; 
           document.body.appendChild(a); 
           a.target = "_blank"; 
           a.click(); 
          } 
         } else { 
          window.location = downloadUrl; 
         } 
        } 

       } catch (ex) { 
        console.log(ex); 
       } 
      } 
     });