qzm
4/23/2017 - 3:32 PM

upload

upload

upload.html
content_copyfile_download
<html>

<body>
    <div id="test-image-preview" style="border: 1px solid rgb(204, 204, 204); width: 100%; height: 200px; background-size: contain; background-repeat: no-repeat; background-position: center center;">
    </div>
    <br/>
    <div id="test-file-info"></div>
    <br/>
    <input type="file" id="test-image-file">
    <script type="text/javascript">
        var   fileInput = document.getElementById('test-image-file'),
              info = document.getElementById('test-file-info'),
              preview = document.getElementById('test-image-preview');
        // 监听change事件:
        fileInput.addEventListener('change', function () {   // 清除背景图片:
              
            preview.style.backgroundImage = '';   // 检查文件是否选择:
              
            if (!fileInput.value) {    
                info.innerHTML = '没有选择文件';    
                return;  
            }   // 获取File引用:
              
            var file = fileInput.files[0];   // 获取File信息:
              
            info.innerHTML = '文件: ' + file.name + '<br>' +            '大小: ' + file.size + '<br>' +            
                '修改: ' + file.lastModifiedDate;  
            if (file.type !== 'image/jpeg' && file.type !== 'image/png' && file.type !== 'image/gif') {    
                alert('不是有效的图片文件!');    
                return;  
            }   // 读取文件:
              
            var reader = new FileReader();  
            reader.onload = function (e) {    
                var       data = e.target.result; // 'data:image/jpeg;base64,/9j/4AAQSk...(base64编码)...'      
                    
                preview.style.backgroundImage = 'url(' + data + ')';  
            };   // 以DataURL的形式读取文件:
              
            reader.readAsDataURL(file);
        });
    </script>

</body>

</html>