csv utf8

@@ -32,6 +32,7 @@ const csvExport = async(res, info = {}) => {
     block.length && data.push(block);
 
     for (let i = 0; i < data.length; i++) {
+        res.write(new Buffer('\xEF\xBB\xBF', 'binary'));
         await res.write(json2csvParser.parse(data[i]));
         await sleep(200); // 解决循环写入cpu占用过高
     }