express之node服务器中的send方法常见的坑！！！

ゝ一世哀愁。 2021-09-17 18:22 518阅读 0赞

### **express中resp.send() 和 resp.json()  这两个方法是响应像客户端发送数据，nodejs是通过流的方式来发送和接收数据的，所以，发送的时候，最终都会，resp.end()结束写入（原生nodejs代码）而resp.send()和 resp.json()两个方法都封装了 end()写入完毕方法，当然不能重复使用！** ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzM0MzE0NA_size_16_color_FFFFFF_t_70][]

### **如果报错以下内容，肯定就是你send方法用了多次！** ###

Error \[ERR\_HTTP\_HEADERS\_SENT\]: Cannot set headers after they are sent to the client  
    at ServerResponse.setHeader (\_http\_outgoing.js:470:11)  
    at ServerResponse.header (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\express\\lib\\response.js:767:10)  
    at ServerResponse.send (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\express\\lib\\response.js:170:12)  
    at done (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\express\\lib\\response.js:1004:10)  
    at tryHandleCache (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\ejs\\lib\\ejs.js:257:5)  
    at View.exports.renderFile \[as engine\] (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\ejs\\lib\\ejs.js:480:10)  
    at View.render (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\express\\lib\\view.js:135:8)  
    at tryRender (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\express\\lib\\application.js:640:10)  
    at Function.render (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\express\\lib\\application.js:592:3)  
    at ServerResponse.render (D:\\GOpath\\src\\KirinProject\\expressServer\\node\_modules\\express\\lib\\response.js:1008:7)

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