Flask笔记：文件上传

 <form action="" method="post" enctype="multipart/form-data">
        <table>
            <tbody>
                <tr>
                    <td>头像：</td>
                    <td><input type="file" name="avatar"></td>
                </tr>
                <tr>
                    <td>描述：</td>
                    <td><input type="text" name="desc"></td>
                </tr>
                <tr>
                    <td></td>
                    <td><input type="submit" value="提交"></td>
                </tr>
            </tbody>
        </table>
    </form>

from wtforms import Form, FileField, StringField
from wtforms.validators import InputRequired
from flask_wtf.file import FileRequired, FileAllowed


class UploadFileForm(Form):
    # FileField表示字段为文件类型
    avatar = FileField(validators=[FileRequired(), FileAllowed([‘jpg‘, ‘png‘, ‘gif‘])])
    # StringField表示字段为字符串类型
    desc = StringField(validators=[InputRequired()])

import os
from werkzeug.utils import secure_filename
from werkzeug.datastructures import CombinedMultiDict
from flask import Flask, request, render_template, send_from_directory
from forms import UploadFileForm

app = Flask(__name__)

# 所有图片文件放在根目录的images文件夹下
UPLOAD_PATH = os.path.join(os.path.dirname(__file__), ‘images‘)


@app.route(‘/upload/‘, methods=[‘GET‘, ‘POST‘])
def upload():
    if request.method == ‘GET‘:
        return render_template(‘upload.html‘)
    else:
        # 结合表单request中的多种表单元素
        form = UploadFileForm(CombinedMultiDict([request.form, request.files]))
        if form.validate():
            # 根据html中对应标签的name属性获取对应上传的数据
            # request.form相当于一个字典
            # desc = request.form.get(‘desc‘)
            desc = form.desc.data
            print(desc)
            # 获取文件需要从request.files中获取
            # avatar = request.files.get(‘avatar‘)
            avatar = form.avatar.data
            # 为了安全起见，需要将文件名使用特殊方式（secure_filename函数）过滤处理一下
            # secure_filename对中文支持不是很好，可以对文件名进行转换，但是仍然推荐使用这个函数来进行处理一下
            filename = secure_filename(avatar.filename)
            # 返回的文件对象可以直接通过它的save方法传入路径保存，路径不能是相对路径，需要是绝对路径
            avatar.save(os.path.join(UPLOAD_PATH, filename))
            return ‘文件上传成功！‘
        else:
            print(form.errors)
            return ‘文件上传失败！‘


@app.route(‘/images/<filename>/‘)
def get_image(filename):
    # 获取文件返回到浏览器中，使用send_from_directory，第一个参数是文件目录，第二个参数是文件名
    return send_from_directory(UPLOAD_PATH, filename)


if __name__ == ‘__main__‘:
    app.run(debug=True)