FormData 获取不到值

Question

<form id="file">
    <input accept="audio/*" name="file" id="test" type="file" />上传语音文件
    <button style="position: absolute;bottom: 0;left: -40px;" @click="test()">上传</button>
</form>

var file = new FormData(document.getElementById("file"));
console.log(file);

https://jsfiddle.net/4g639vwz/

为啥获取不到值，打印的是空的！

Answer 1

你要这样打印：

for (var [key, value] of file.entries()) { 
  console.log(key, value);
}

Answer 2

复制测试看下

    <input type="file" id="file">


<script>
    var input = document.getElementById('file');
    input.addEventListener('change', function(e){
        var file = e.target.files[0];

        var formData = new FormData();
        formData.append('file', file);
        for (var value of formData.values()) {
        console.log(value); 
        }
        
    }, false);
</script>

Answer 3

你那input的id是test