在javascript fetch POST请求中向flask服务器传递头部和文件

// 创建FormData对象
var formData = new FormData();

// 添加文件到FormData对象
var fileInput = document.getElementById('fileInput'); // 假设有一个文件输入框
var file = fileInput.files[0];
formData.append('file', file);

// 添加请求头到FormData对象
formData.append('header1', 'value1');
formData.append('header2', 'value2');

// 发送POST请求
fetch('/api/upload', {
  method: 'POST',
  body: formData
})
.then(response => response.json())
.then(data => {
  // 处理响应数据
})
.catch(error => {
  // 处理错误
});

from flask import Flask, request

app = Flask(__name__)

@app.route('/api/upload', methods=['POST'])
def upload():
    file = request.files['file']
    header1 = request.headers.get('header1')
    header2 = request.headers.get('header2')

    # 处理文件和请求头
    # ...

    return 'Success'

if __name__ == '__main__':
    app.run()