JS小白~对网上的一段代码加以改造想要实现多张图片上传预览效果

$("#uploadImage").on("change", function(){
// Get a reference to the fileList
var files = !!this.files ? this.files : [];

// If no files were selected, or no FileReader support, return
if (!files.length || !window.FileReader) return;

// Only proceed if the selected file is an image
if (/^image/.test( files[0].type)){

    // Create a new instance of the FileReader
    var reader = new FileReader();

    // Read the local file as a DataURL
    reader.readAsDataURL(files[0]);

    // When loaded, set image data as background of p
    reader.onloadend = function(){
   $("#uploadPreview").css("background-image","url("+this.result+")");
    }
}});

于是问题出现了：目前最近上传的是考拉图片，下一张再选择上传考拉图片---结果失败。必须上传另一张图片后才能上传考拉图片。

该如何解决？