$("input[name='file']").on("change", function() {
        upload();
    })
function upload() {
        var index = layer.load();
        var formData = new FormData();
        formData.append("file", document.getElementById("file1").files[0]);
        formData.append("_token", $("input[name='_token']").val());
        $.ajax({
            url: "{{route('home.public.upload')}}",
            type: "POST",
            data: formData,
            contentType: false,
            processData: false,
            success: function(data) {
                if (data.code == 0) {
                    $("input[name='certification']").val(data.data)
                    $(".imgs").find("img").attr("src", data.data);
                }
                layer.close(index);
            },
            error: function() {
                alert("上传失败!");
                layer.close(index);
            }
        });
    }


多文件上传

<!doctype html>
<html lang="zh">
<head>
  <meta charset="utf-8">
  <title>多文件上传</title>
  <script src="jquery.js"></script>
  <script>
   $(function(){
         $("#btn").click(function(){
               var formData = new FormData();
               for(var i=0; i<$('#file')[0].files.length;i++){
                   formData.append('file[]', $('#file')[0].files[i]);
               }
               $.ajax({
                  url: "test.php",
                  type: "POST",
                  processData: false,
                  contentType: false,
                  data: formData,
                  success: function(d){

                  }
               });

          });

   })

  </script>
</head>
<body>
    <form>    
     <input  type="file" multiple id="file" name="file[]" > 
     <input  type="button" id="btn" value="提交"/>
    </form>
</body>