场景使用&解释

通过ajax请求是否符合下载文件，并且获取ajax返回的文件链接进行下载操作代码。

代码串

/**
 * @name uxdown(file) 下载文件
 * @author flower
 * @mtime 2022-10-14
 * @param file string
 * @return file
 */
function uxdown(file)
{
   var URLToPDF = file;
   var theFileName = URLToPDF.substring(URLToPDF.lastIndexOf('/') + 1, URLToPDF.length);
   var URL = window.URL || window.webkitURL;
   var oReq = new XMLHttpRequest();
   oReq.open("GET", URLToPDF, true);
   oReq.responseType = "blob";
   oReq.onload = function() {
      var file = new Blob([oReq.response], { 
         type: 'application/pdf' 
      });
      saveAs(file, theFileName);
   };
   oReq.send();
}
function saveAs(blob, filename) {
    var type = blob.type;
    var force_saveable_type = 'application/octet-stream';
    if (type && type != force_saveable_type) {
        var slice = blob.slice || blob.webkitSlice || blob.mozSlice;
        blob = slice.call(blob, 0, blob.size, force_saveable_type);
    }
    var url = URL.createObjectURL(blob);
    var save_link = document.createElementNS('http://www.w3.org/1999/xhtml', 'a');
    save_link.href = url;
    save_link.download = filename;

    var event = new MouseEvent("click", {
            bubbles: true,
            cancelable: true,
            view: window
        });
    save_link.dispatchEvent(event);
    URL.revokeObjectURL(url);
}