Java 通过base64编码在前端展示图片

1、java

public static String ImageToBase64(String src){
            if (src == "" || src == null) {
                return "";
            }

            File file = new File(src);
            if (!file.exists()) {
                return "";
            }

            byte [] data = null;
            try {
                FileInputStream fis = new FileInputStream(src);
                data = new byte[fis.available()];
                fis.read(data);
                fis.close();
            } catch (IOException e) {
                e.printStackTrace();
            }

            BASE64Encoder base64Encoder = new BASE64Encoder();
            return base64Encoder.encode(data);
        }

2、js

 $("#showPic").append("<img class="layui-upload-img" id="showPic" src="data:image/png;base64,"+ src1 + "" height='40px' width='120px'>");

格式：

<img src="data:image/png;base64,从后台获取的base编码" />