• Django 图片上传和下载功能


    Django 实现图片上传功能

    原生上传图片方式

    #新建工程 
    python manage.py startapp test30
    #修改 settings.py
    INSTALLED_APPS = [
        'django.contrib.admin',
        'django.contrib.auth',
        'django.contrib.contenttypes',
        'django.contrib.sessions',
        'django.contrib.messages',
        'django.contrib.staticfiles',
        'stu'
    ]
    #修改urls.py
    from django.conf.urls import url, include
    from django.contrib import admin
    
    urlpatterns = [
        url(r'^admin/', admin.site.urls),
        url(r'student/',include('stu.urls')),
    ]
    #新增加 stu/urls.py 
    #coding:utf-8
    from django.conf.urls import url
    import views
    urlpatterns = [
        url(r'^$',views.index_view)
    ]
    #编辑 stu/views.py 
    # -*- coding: utf-8 -*-
    from __future__ import unicode_literals
    
    from django.http import HttpResponse
    from django.shortcuts import render
    
    # Create your views here.
    #原生上传文件方式
    def index_view(request):
        if request.method == 'GET':
           return render(request,'index.html')
        elif request.method == 'POST':
            #获取请求参数
            uname = request.POST.get('uname','')
            photo = request.FILES.get('photo','')
            print photo.name
            import os
            print os.getcwd()
            if not os.path.exists('media'):
                 os.mkdir('media')
            #拼接路径
            with open(os.path.join(os.getcwd(),'media',photo.name),'wb') as fw:
                # photo.read() #一次性读取文件到内存
                # fw.write(photo.read())
    
                #分块读取,性能高
                for ck in photo.chunks():
                    fw.write(ck)
    
            return HttpResponse('It is post request,上传成功')
    
        else:
            return HttpResponse('It is not post and get request!')
    #新增加模板文件 templates/index.html
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    <form action="/student/" method="post" enctype="multipart/form-data">
        {% csrf_token %}
        <p>
            <label for="ua">姓名: </label> <input type="text" name="uname" id="ua"/>
        </p>
        <p>
            <label for="ph">头像: </label> <input type="file" name="photo" id="ph"/>
        </p>
        <p>
            &emsp;&emsp;&emsp;&emsp;&emsp;<input type="submit" value="注册"/>
        </p>
    </form>
    </body>
    </html>
    #效果如下:
    访问:  http://127.0.0.1:8000/student/
    

    Django 图片上传方式

    需求:
    效果: 访问 http://127.0.0.1:8000/student/ 通过注册将姓名、头像地址传入数据库中;
    访问 http://127.0.0.1:8000/student/showall 将数据库信息通过表格形式展示
    
    ###过程
    #修改 settings.py ,templates 新增加 'django.template.context_processors.media'
    TEMPLATES = [
        {
            'BACKEND': 'django.template.backends.django.DjangoTemplates',
            'DIRS': [os.path.join(BASE_DIR, 'templates')]
            ,
            'APP_DIRS': True,
            'OPTIONS': {
                'context_processors': [
                    'django.template.context_processors.debug',
                    'django.template.context_processors.request',
                    'django.contrib.auth.context_processors.auth',
                    'django.contrib.messages.context_processors.messages',
                    'django.template.context_processors.media'
                ],
            },
        },
    ]
    
    末尾增加:
    # global_settings
    #指定上传文件存储相对路径(读取文件)
    MEDIA_URL = '/media/'
    #指定上传文件存储绝对路径(存储文件)
    MEDIA_ROOT = os.path.join(BASE_DIR,'media')
    
    #创建数据库模型 stu/models.py
    # -*- coding: utf-8 -*-
    from __future__ import unicode_literals
    
    from django.db import models
    
    # Create your models here.
    
    class Student(models.Model):
        sno = models.AutoField(primary_key=True)
        sname = models.CharField(max_length=30)
        photo = models.ImageField(upload_to='imgs')
    
        def __unicode__(self):
            return u'Student:%s'%self.sname
    #生成数据库迁移文件,查看数据库表结构
    python makemigrations stu
    python migrate 
    
    
    #修改 urls.py  因为显示问题,增加 DEBUG 内容
    from django.conf.urls import url, include
    from django.contrib import admin
    
    from test30.settings import DEBUG, MEDIA_ROOT
    
    urlpatterns = [
        url(r'^admin/', admin.site.urls),
        url(r'student/',include('stu.urls')),
    ]
    from django.views.static import serve
    if DEBUG:
        urlpatterns+=url(r'^media/(?P<path>.*)/$', serve, {"document_root": MEDIA_ROOT}),
    
    #修改 urls, stu/urls.py
    #coding:utf-8
    from django.conf.urls import url
    import views
    urlpatterns = [
        url(r'^$',views.index_view),
        url(r'^upload/$',views.upload_view),
        url(r'^showall/$',views.showall_view)
    ]
    
    # 修改 stu/views.py
    #django 上传文件方式
    def upload_view(request):
        uname = request.POST.get('uname','')
        photo = request.FILES.get('photo','')
        #入库操作
        Student.objects.create(sname=uname,photo=photo)
        return HttpResponse('上传成功!')
    
    #显示图片
    def showall_view(request):
        stus = Student.objects.all()
        print stus
        return render(request,'show.html',{'stus':stus})
    
    # 修改 index.html
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    <form action="/student/upload/" method="post" enctype="multipart/form-data">
        {% csrf_token %}
        <p>
            <label for="ua">姓名: </label> <input type="text" name="uname" id="ua"/>
        </p>
        <p>
            <label for="ph">头像: </label> <input type="file" name="photo" id="ph"/>
        </p>
        <p>
            &emsp;&emsp;&emsp;&emsp;&emsp;<input type="submit" value="注册"/>
        </p>
    </form>
    </body>
    </html>
    # 增加模板文件 show.html
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    <table width="500px" border="1" cellspacing="0">
        <tr>
            <th>编号</th>
            <th>姓名</th>
            <th>头像</th>
            <th>操作</th>
        </tr>
        {% for stu in stus %}
        <tr>
        <td>{{ forloop.counter }}</td>
        <td>{{ stu.sname }}</td>
        <td><img style=" 200px;" src="{{ MEDIA_URL }}{{ stu.photo }}"/></td>
        <td> 下载</td>
        </tr>
        {% endfor %}
    
    </table>
    </body>
    </html>
    效果图:
    http://127.0.0.1:8000/student/ 注册实现数据库录入操作(点击提交通过index.html 中action="/student/upload/"  将url 转发至函数upload_view ,实现上传功能)
    http://127.0.0.1:8000/student/showall/ 实现数据库信息展示
    


    图片下载功能

    ### 需求
    在显示页面点击下载实现图片的下载功能
    过程:
    
    #修改 show.html ,加入 下载的超链接
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    <table width="500px" border="1" cellspacing="0">
        <tr>
            <th>编号</th>
            <th>姓名</th>
            <th>头像</th>
            <th>操作</th>
        </tr>
        {% for stu in stus %}
        <tr>
        <td>{{ forloop.counter }}</td>
        <td>{{ stu.sname }}</td>
        <td><img style=" 200px;" src="{{ MEDIA_URL }}{{ stu.photo }}"/></td>
        <td><a href="/student/download/?photo={{ stu.photo }}">下载</a></td>
        </tr>
        {% endfor %}
    
    </table>
    </body>
    </html>
    
    
    #因为 show.html href="/student/download  ,所以要修改urls
    #修改 stu/urls.py,新增加 url
    url(r'^download/$',views.download_view)
    
    #修改 stu/views.py
    
    def download_view(request):
        # 获取请求参数(图片存储位置) imgs/5566.jpg
        photo = request.GET.get('photo','')
        print photo
    
        # 获取图片文件名5566.jpg ; rindex 为字符 '/' 在 photo 中最后出现的位置索引;例如
        # txt = "imgs/5566.jpg"
        # x = txt.rindex("/")
        # print txt[x + 1:]   输出结果为 5566.jpg
        filename = photo[photo.rindex('/')+1:]
        print filename
        #开启一个流
        import os
        path = os.path.join(os.getcwd(),'media',photo.replace('/','\'))
        print path
    
        with open(path,'rb') as fr:
            response = HttpResponse(fr.read())
            response['Content-Type']='image/png'
            response['Content-Disposition'] = 'attachment;filename=' + filename
    
        return response
    
    #访问 http://127.0.0.1:8000/student/showall/ ,点击下载
    

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  • 原文地址:https://www.cnblogs.com/lixinliang/p/14108663.html
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