本文实例讲述了Nodejs处理异常操作。分享给大家供大家参考，具体如下：
Exception.js
module.exports = {
expfun: function(flag) {
if(flag == 0) {
throw '我是error';
}
return "success";
}
}
optfile.js
//-------------optfile.js-------------------------
var fs = require('fs');
module.exports = {
readfile: function (path, recall) { //异步执行
fs.readFile(path, function (err, data) {
if (err) {
console.log("异步执行error：" err);
recall("文件不存在，异步执行error：" err);//异步处理异常
} else {
//console.log(data.toString());
recall(data);
}
});
console.log("===异步方法执行完毕===");
},
readImg: function (path, res) {
fs.readFile(path, 'binary', function (err, filedata) {
if (err) {
console.log(err);
return;
} else {
console.log("输出文件");
res.write(filedata, 'binary');
res.end();
}
});
}
}
router.js
var optfile = require('../model/optfile2.js');
function getRecall(req, res) {
res.writeHead(200, {
'Content-Type': 'text/html; charset=utf-8'
});
function recall(data) {
res.write(data);
res.end(''); //不写则没有http协议尾
}
return recall;
}
module.exports = {
login: function (req, res) {
recall = getRecall(req, res);
optfile.readfile('./view/login.html', recall);
},
showimg: function (req, res) {
res.writeHead(200, {
'Content-Type': 'image/jpeg'
});
optfile.readImg("./view/pig.png", res);
}
}
//-------------n9_exception.js---------------
/*
同步的捕获&&异步的捕获
*/
var http = require('http');
var url = require('url');
var router = require('./model/router');
var exception = require('./model/Exception');
http.createServer(function (request, response) {
if (request.url !== "/favicon.ico") { //清除第2此访问
pathname = url.parse(request.url).pathname;
pathname = pathname.replace(/\//, ''); //替换掉前面的/
try {
router[pathname](request, response);
// data = exception.expfun(0);
// response.write(data);
// response.end('');
} catch (err) {
console.log('捕获到异常=' err);
response.writeHead(200, {
'Content-Type': 'text/html; charset=utf-8'
});
response.write(err.toString());
response.end('');
}
console.log("server执行完毕");
}
}).listen(8000);
console.log('Server running at http://127.0.0.1:8000/');
希望本文所述对大家nodejs程序设计有所帮助。