Question

window.print（）函数弹出打印屏幕，但我想在弹出window.print myFunction（）之前完成它的过程。所以我的程序等待完成myFunction。

(function () {
    var beforePrint = function () {
        console.log('Functionality to run after printing');
        myFunction();
        //window.print() pop up should wait until myFunction() finish
    };

    var afterPrint = function () {
        console.log('Functionality to run after printing');
    };

    if (window.matchMedia) {
        var mediaQueryList = window.matchMedia('print');
        mediaQueryList.addListener(function (mql) {
            if (mql.matches) {
                beforePrint();
            } else {
                afterPrint();
            }
        });
    }

    window.onbeforeprint = beforePrint;
    window.onafterprint = afterPrint;

}());

Answer 1

您可以使用jquerys deferred / then功能在打印前执行操作。像这样：

$(function() {
  var filterResolve = function() {
    var defer = $.Deferred(),
      filtered = defer.then(function(value) {
      //do lengthy stuff here
        alert('Before Print');
        return true;
        //or false if you don't want to print
      });
    defer.resolve();
    filtered.done(function(value) {
      if (value == true) {
        window.print();
              //here you can log that the print dialog was shown to the user
             //but not if he hit OK or Cancel
      }
    });
  };
  $("button").on("click", filterResolve);
});

但据我所知，（在任何浏览器中）都无法检测是否打印了任何内容。即使用户在打印对话框中单击“确定”或“取消”也不行。

哦，是的，here's a quiet useless plunker

在window.print弹出之前等window.onbeforeprint？

1 个答案: