ES6语法异步转同步
2018-12-17 本文已影响0人
全都是泡沫啦
<!DOCTYPE html>
<script src="http://code.jquery.com/jquery-2.1.4.min.js"></script>
<script>
function getAjax(url){
return new Promise((resolve,reject)=>{
let xhr = new XMLHttpRequest();
xhr.onreadystatechange=function(){
if(xhr.readyState === 4){
if(xhr.status===200){
let text = xhr.responseText;
let data = JSON.parse(text);
resolve(data);
}else{
reject("ajax请求发送失败");
}
}
};
xhr.open("get",url);
xhr.send();
});
}
function getAjaxJquery(url){
return $.ajax({url,async:true});
}
// getAjaxJquery("http://127.0.0.1:9000/test1").then(
// (data)=>{
// debugger
// }
// )
// getAjax("http://127.0.0.1:9000/test1").then(
// (data)=>{
// debugger
// }
// )
async function test(){
let data = await getAjaxJquery("http://127.0.0.1:9000/test1");
console.log("1:"+data)
let data2 = null;
if(data.type == "test2"){
console.log("2.1")
data2 = await getAjaxJquery(`http://127.0.0.1:9000/test2`);
}else if(data.type == "test3"){
console.log("2.2")
data2 = await getAjaxJquery(`http://127.0.0.1:9000/test3`);
}
console.log("2:"+data2)
console.log("3")
}
// test()//test内部是同步,外层调用test()是异步
// console.log("执行123")
function *Test2(){
console.log("=====1:")
let data1 = yield getAjax("http://127.0.0.1:9000/test1");
let data2 = null;
if(data1.type == "test2"){
console.log("=====2.1")
data2 = yield getAjax(`http://127.0.0.1:9000/test2`);
console.log("=====2.1.1")
}else if(data1.type == "test3"){
console.log("=====2.2")
data2 = yield getAjax(`http://127.0.0.1:9000/test3`);
console.log("=====2.2.2")
}
console.log("=====2:"+data2)
return "=====123";
}
if(false){
let test2 = Test2();
test2.next() //test2.next() = getAjax("http://127.0.0.1:9000/test1")
.value.then(
(data11) => {//data12为test1接口返回的数据
let result = test2.next(data11); //data11:会传入到 *Test2中let data1 = data11
//test2.next(data) = getAjax(`http://127.0.0.1:9000/test2`)
//test2.next(data) = getAjax(`http://127.0.0.1:9000/test3`)
return result.value;
},
null
).then(
(data22) => {//data22为接口test2或者test3的接口返回的数据
let result = test2.next(data22); //data22:会传入到 *Test2中let data2 = data22
//result为*Test2的return
console.log("result:"+result.value)
}
,
null
)
}
function *Test3(){
console.log("+++++1:")
let data = yield getAjaxJquery("http://127.0.0.1:9000/test1");
let data2 = null;
if(data.type == "test2"){
console.log("+++++2.1")
data2 = yield getAjaxJquery(`http://127.0.0.1:9000/test2`);
console.log("+++++2.1.1")
}else if(data.type == "test3"){
console.log("+++++2.2")
data2 = yield getAjaxJquery(`http://127.0.0.1:9000/test3`);
console.log("+++++2.2.2")
}
console.log("+++++2:"+data2)
return "+++++123";
}
let test3 = Test3();
let z1 = test3.next();
console.log("+++++z1:"+z1);
z1.value.then(
(data) => {
return test3.next(data).value;
}
).then(
(data) => {
let result = test3.next(data).value;
console.log(result)
}
)
console.log("end...")
</script>
</html>
package com.example.testweb;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
@SpringBootApplication
@RestController
public class TestwebApplication {
@RequestMapping("/test1")
public Map<String, Object> test1(){
HashMap<String, Object> objectObjectHashMap = new HashMap<>();
objectObjectHashMap.put("type","test2");
return objectObjectHashMap;
}
@RequestMapping("/test2")
public Map<String, Object> test2(){
HashMap<String, Object> objectObjectHashMap = new HashMap<>();
objectObjectHashMap.put("name","张三");
objectObjectHashMap.put("age",18);
return objectObjectHashMap;
}
@RequestMapping("/test3")
public Map<String, Object> test3(){
HashMap<String, Object> objectObjectHashMap = new HashMap<>();
objectObjectHashMap.put("name","李四");
objectObjectHashMap.put("age",20);
return objectObjectHashMap;
}
@Bean
public FilterRegistrationBean testFilterRegistration() {
FilterRegistrationBean registration = new FilterRegistrationBean();
registration.setFilter(new ApiOriginFilter());
registration.addUrlPatterns("/*");
registration.setName("corsFilter");
registration.setOrder(1);
return registration;
}
public static void main(String[] args) {
SpringApplication.run(TestwebApplication.class, args);
}
public static class ApiOriginFilter implements Filter {
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse res = (HttpServletResponse) response;
res.addHeader("Access-Control-Allow-Origin", req.getHeader("Origin"));
res.addHeader("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT");
res.addHeader("Access-Control-Allow-Headers", "Content-Type");
res.addHeader("Access-Control-Allow-Credentials", "true");
chain.doFilter(request, response);
}
@Override
public void destroy() {
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
}
}
