javascript - 在 jquery 获取请求中从 for 循环调用 var i

Question

我在 $.get 的范围内访问 var i 时遇到问题。这是我的代码：

for (var i = 0; i < printer_ids.length; i++) {
  $.get('/get_printer_status_message/'+printer_ids[i]+'/', function(data) {
    $('#printer_status_'+printer_ids[i]).html(data);

    console.log(data)
    console.log('id: #printer_status_'+printer_ids[i]);
    console.log('current:' + $('#printer_status_'+printer_ids[i]).html());
  });
}

i 在 $.get 行中定义，但不在 $.get 的范围内。如何在 $.get 的范围内访问 var i？

Answer 1

一个更好的重构，避免在每圈重新定义函数：

var doIt = function (printer_id){
    $.get('/get_printer_status_message/'+printer_id]+'/', function(data) {
      $('#printer_status_'+printer_id).html(data);

      console.log(data)
      console.log('id: #printer_status_'+printer_id);
      console.log('current:' + $('#printer_status_'+printer_id).html());
    });
};

for (var i = 0; i < printer_ids.length; i++) {
    doIt(printer_ids[i]);
}

Answer 2

您必须i在本地范围内捕获变量：

for (var i = 0; i < printer_ids.length; i++) {
  (function (i){
    $.get('/get_printer_status_message/'+printer_ids[i]+'/', function(data) {
      $('#printer_status_'+printer_ids[i]).html(data);

      console.log(data)
      console.log('id: #printer_status_'+printer_ids[i]);
      console.log('current:' + $('#printer_status_'+printer_ids[i]).html());
    });
  }(i));
}