在使用angular2进行图片上传的时候，遇到了各种各样的问题。在多番尝试之后最终成功上传图片，下面将我的方法分享给大家：
文件系统模块
const fs = require('fs');
//引入body-parser
//包含在请求正文中提交的键/值对数据。
//默认情况下，它是未定义的，并在使用body-parser中间件时填充。
var bodyParser = require('body-parser');
var app = express();
//解析 application/x-www-form-urlencoded，limit:'20mb'用于设置请求的大小
//解决nodejs Error: request entity too large问题
app.use(bodyParser.urlencoded({ limit:'20mb',extended: true }));
//设置跨域访问
app.all('*',function(req,res,next) {
res.header("Access-Control-Allow-Origin","*");
res.header("Access-Control-Allow-Headers","X-Requested-With");
res.header("Access-Control-Allow-Methods","PUT,POST,GET,DELETE,OPTIONS");
res.header("Content-Type","application/json;charset=utf-8");
next();
});
//上传图片
app.post('/upload',res){
var imgData = req.body.url;
var base64Data = imgData.replace(/^data:image\/\w+;base64,/,"");
var dataBuffer = new Buffer(base64Data,'base64');
fs.writeFile("image.png",dataBuffer,function(err) {
if(err){
res.send(err);
}else{
res.send("保存成功！");
}
});
})
var server = app.listen(4444,function() {
console.log('监听端口 4444');
});
uploadImage(data) {
return new Promise((resolve,reject) => {
let headers = new Headers({
'Content-Type': 'application/x-www-form-urlencoded'
});
let options = new RequestOptions({
headers: headers
});
this.http.post("http://localhost:4444/upload",this.toQueryString(data),options)
.map(res => res.json())
.subscribe(data => { resolve(data),error => { reject(error) } })
})
}
return new Promise((resolve,reject) => {
let headers = new Headers({
'Content-Type': 'application/x-www-form-urlencoded'
});
let options = new RequestOptions({
headers: headers
});
this.http.post("http://localhost:4444/upload",this.toQueryString(data),options)
.map(res => res.json())
.subscribe(data => { resolve(data),error => { reject(error) } })
})
}
// JSON参数序列化
private toQueryString(obj) {
let result = [];
for (let key in obj) {
key = encodeURIComponent(key);
let values = obj[key];
if (values && values.constructor == Array) {
let queryValues = [];
for (let i = 0,len = values.length,value; i < len; i++) {
value = values[i];
queryValues.push(this.toQueryPair(key,value));
}
result = result.concat(queryValues);
} else {
result.push(this.toQueryPair(key,values));
}
}
return result.join('&');
}
private toQueryPair(key,value) {
if (typeof value == 'undefined') {
return key;
}
return key + '=' + encodeURIComponent(value === null ? '' : String(value));
}
