axios基本使用-阿里云开发者社区

axios基本使用

简介

Axios，是一个基于promise 的网络请求库，作用于node.js和浏览器中，它是 isomorphic 的(即同一套代码可以运行在浏览器和node.js中)。在服务端它使用原生node.js http模块, 而在客户端 (浏览端) 则使用XMLHttpRequest。

特点：

从浏览器创建 XMLHttpRequests
从 node.js 创建 http 请求
支持 Promise API
拦截请求和响应
转换请求和响应数据
取消请求
自动转换JSON数据
客户端支持防御XSRF

总结：对ajax的优化。

基础语法

首先是需要导入相关的js文件

axios-0.18.0.js

/* axios v0.18.0 | (c) 2018 by Matt Zabriskie */
!function(e,t){"object"==typeof exports&&"object"==typeof module?module.exports=t():"function"==typeof define&&define.amd?define([],t):"object"==typeof exports?exports.axios=t():e.axios=t()}(this,function(){return function(e){function t(r){if(n[r])return n[r].exports;var o=n[r]={exports:{},id:r,loaded:!1};return e[r].call(o.exports,o,o.exports,t),o.loaded=!0,o.exports}var n={};return t.m=e,t.c=n,t.p="",t(0)}([function(e,t,n){e.exports=n(1)},function(e,t,n){"use strict";function r(e){var t=new s(e),n=i(s.prototype.request,t);return o.extend(n,s.prototype,t),o.extend(n,t),n}var o=n(2),i=n(3),s=n(5),u=n(6),a=r(u);a.Axios=s,a.create=function(e){return r(o.merge(u,e))},a.Cancel=n(23),a.CancelToken=n(24),a.isCancel=n(20),a.all=function(e){return Promise.all(e)},a.spread=n(25),e.exports=a,e.exports.default=a},function(e,t,n){"use strict";function r(e){return"[object Array]"===R.call(e)}function o(e){return"[object ArrayBuffer]"===R.call(e)}function i(e){return"undefined"!=typeof FormData&&e instanceof FormData}function s(e){var t;return t="undefined"!=typeof ArrayBuffer&&ArrayBuffer.isView?ArrayBuffer.isView(e):e&&e.buffer&&e.buffer instanceof ArrayBuffer}function u(e){return"string"==typeof e}function a(e){return"number"==typeof e}function c(e){return"undefined"==typeof e}function f(e){return null!==e&&"object"==typeof e}function p(e){return"[object Date]"===R.call(e)}function d(e){return"[object File]"===R.call(e)}function l(e){return"[object Blob]"===R.call(e)}function h(e){return"[object Function]"===R.call(e)}function m(e){return f(e)&&h(e.pipe)}function y(e){return"undefined"!=typeof URLSearchParams&&e instanceof URLSearchParams}function w(e){return e.replace(/^\s*/,"").replace(/\s*$/,"")}function g(){return("undefined"==typeof navigator||"ReactNative"!==navigator.product)&&("undefined"!=typeof window&&"undefined"!=typeof document)}function v(e,t){if(null!==e&&"undefined"!=typeof e)if("object"!=typeof e&&(e=[e]),r(e))for(var n=0,o=e.length;n<o;n++)t.call(null,e[n],n,e);else for(var i in e)Object.prototype.hasOwnProperty.call(e,i)&&t.call(null,e[i],i,e)}function x(){function e(e,n){"object"==typeof t[n]&&"object"==typeof e?t[n]=x(t[n],e):t[n]=e}for(var t={},n=0,r=arguments.length;n<r;n++)v(arguments[n],e);return t}function b(e,t,n){return v(t,function(t,r){n&&"function"==typeof t?e[r]=E(t,n):e[r]=t}),e}var E=n(3),C=n(4),R=Object.prototype.toString;e.exports={isArray:r,isArrayBuffer:o,isBuffer:C,isFormData:i,isArrayBufferView:s,isString:u,isNumber:a,isObject:f,isUndefined:c,isDate:p,isFile:d,isBlob:l,isFunction:h,isStream:m,isURLSearchParams:y,isStandardBrowserEnv:g,forEach:v,merge:x,extend:b,trim:w}},function(e,t){"use strict";e.exports=function(e,t){return function(){for(var n=new Array(arguments.length),r=0;r<n.length;r++)n[r]=arguments[r];return e.apply(t,n)}}},function(e,t){function n(e){return!!e.constructor&&"function"==typeof e.constructor.isBuffer&&e.constructor.isBuffer(e)}function r(e){return"function"==typeof e.readFloatLE&&"function"==typeof e.slice&&n(e.slice(0,0))}/*!
 * Determine if an object is a Buffer
 *
 * @author   Feross Aboukhadijeh <https://feross.org>
 * @license  MIT
 */
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e?(r.forEach(e.split("\n"),function(e){if(i=e.indexOf(":"),t=r.trim(e.substr(0,i)).toLowerCase(),n=r.trim(e.substr(i+1)),t){if(s[t]&&o.indexOf(t)>=0)return;"set-cookie"===t?s[t]=(s[t]?s[t]:[]).concat([n]):s[t]=s[t]?s[t]+", "+n:n}}),s):s}},function(e,t,n){"use strict";var r=n(2);e.exports=r.isStandardBrowserEnv()?function(){function e(e){var t=e;return n&&(o.setAttribute("href",t),t=o.href),o.setAttribute("href",t),{href:o.href,protocol:o.protocol?o.protocol.replace(/:$/,""):"",host:o.host,search:o.search?o.search.replace(/^\?/,""):"",hash:o.hash?o.hash.replace(/^#/,""):"",hostname:o.hostname,port:o.port,pathname:"/"===o.pathname.charAt(0)?o.pathname:"/"+o.pathname}}var t,n=/(msie|trident)/i.test(navigator.userAgent),o=document.createElement("a");return t=e(window.location.href),function(n){var o=r.isString(n)?e(n):n;return o.protocol===t.protocol&&o.host===t.host}}():function(){return function(){return!0}}()},function(e,t){"use strict";function n(){this.message="String contains an 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s(t)||(r(e),t&&t.response&&(t.response.data=i(t.response.data,t.response.headers,e.transformResponse))),Promise.reject(t)})}},function(e,t,n){"use strict";var r=n(2);e.exports=function(e,t,n){return r.forEach(n,function(n){e=n(e,t)}),e}},function(e,t){"use strict";e.exports=function(e){return!(!e||!e.__CANCEL__)}},function(e,t){"use strict";e.exports=function(e){return/^([a-z][a-z\d\+\-\.]*:)?\/\//i.test(e)}},function(e,t){"use strict";e.exports=function(e,t){return t?e.replace(/\/+$/,"")+"/"+t.replace(/^\/+/,""):e}},function(e,t){"use strict";function n(e){this.message=e}n.prototype.toString=function(){return"Cancel"+(this.message?": "+this.message:"")},n.prototype.__CANCEL__=!0,e.exports=n},function(e,t,n){"use strict";function r(e){if("function"!=typeof e)throw new TypeError("executor must be a function.");var t;this.promise=new Promise(function(e){t=e});var n=this;e(function(e){n.reason||(n.reason=new o(e),t(n.reason))})}var o=n(23);r.prototype.throwIfRequested=function(){if(this.reason)throw this.reason},r.source=function(){var e,t=new r(function(t){e=t});return{token:t,cancel:e}},e.exports=r},function(e,t){"use strict";e.exports=function(e){return function(t){return e.apply(null,t)}}}])});
//# sourceMappingURL=axios.min.map

这篇文章的特点在于，是对于这一篇文章Ajax的基础使用，将这篇文章中的内容使用axios，进行优化。大家学完了之后可以，看一下这一篇文章进行练习一下。

springboot+vue+mybatis-plus+axios实现商品的CRUD

项目创建

第一步：

第二步：

添加配置文件各种依赖

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.example</groupId>
  <artifactId>AjaxStudy</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>AjaxStudy Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <properties>
    <maven.compiler.source>8</maven.compiler.source>
    <maven.compiler.target>8</maven.compiler.target>
  </properties>
  <dependencies>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.1.0</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>fastjson</artifactId>
      <version>1.2.62</version>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.tomcat.maven</groupId>
        <artifactId>tomcat7-maven-plugin</artifactId>
        <version>2.2</version>
      </plugin>
    </plugins>
  </build>
</project>

案例

这个案例的目的就是完成我们常见的像百度啊，那种点击搜索栏就会出现提示词那种异步请求，网页没有刷新，但是确实响应了，然后紧跟时代，这个案例我使用SpringBoot来做，最开始用的还是传统的MVC，但是说实话，太麻烦了，一大堆配置，调试都要半天。

数据库建表语句

/*
 Navicat MySQL Data Transfer
 Source Server         : 本机
 Source Server Type    : MySQL
 Source Server Version : 80024
 Source Host           : localhost:3306
 Source Schema         : projectdatabase
 Target Server Type    : MySQL
 Target Server Version : 80024
 File Encoding         : 65001
 Date: 11/01/2023 20:27:49
*/
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for user
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user`  (
  `id` int NOT NULL AUTO_INCREMENT,
  `username` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `password` varchar(200) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 3 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = DYNAMIC;
-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES (1, 'LIHUA', '123456');
INSERT INTO `user` VALUES (2, 'zhangsan', '123');
INSERT INTO `user` VALUES (3, 'LISI', '456489');
INSERT INTO `user` VALUES (4, 'heheheh', '123456');
INSERT INTO `user` VALUES (5, 'ahuang', '123');
INSERT INTO `user` VALUES (6, 'dsdad', '154654');
SET FOREIGN_KEY_CHECKS = 1;

项目结构

一定注意一点，就是这个后端的java类，一定要写在Springbootlogincheck包下面，不然会导致网址访问不到404错误。

User类

package com.example.springbootlogincheck.Bean;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private Integer id;
    private String username;
    private String password;
}

IndexController类

package com.example.springbootlogincheck.Controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
@Controller
public class IndexController {
    @RequestMapping("/")
    public String index(){
        return"admin/register.html";
    }
}

UserController

package com.example.springbootlogincheck.Controller;
import com.example.springbootlogincheck.Bean.User;
import com.example.springbootlogincheck.Dao.UserDao;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedReader;
import java.io.IOException;
import java.util.List;
@Controller
public class UserController {
    @Autowired
    UserDao userDao;
    @ResponseBody
    @GetMapping("/selectUser")
    public Boolean SelectUser(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String username = request.getParameter("username");
        System.out.println(username);
        boolean flag = false;
        List<User> list = userDao.selectList(null);
        for (User user : list){
            if (user.getUsername().equals(username)){
                flag = true;
            }
        }
        System.out.println(flag);
        if (flag) {
//            response.reset();
            return true;
        }
        return false;
    }
}

UserDao

package com.example.springbootlogincheck.Dao;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.example.springbootlogincheck.Bean.User;
import org.apache.ibatis.annotations.Mapper;
@Mapper
public interface UserDao extends BaseMapper<User> {
}

前端网页

register.css

* {
    margin: 0;
    padding: 0;
    list-style-type: none;
}
.reg-content{
    padding: 30px;
    margin: 3px;
}
a, img {
    border: 0;
}
body {
    background-image: url("../imgs/reg_bg_min.jpg") ;
    text-align: center;
}
table {
    border-collapse: collapse;
    border-spacing: 0;
}
td, th {
    padding: 0;
    height: 90px;
}
.inputs{
    vertical-align: top;
}
.clear {
    clear: both;
}
.clear:before, .clear:after {
    content: "";
    display: table;
}
.clear:after {
    clear: both;
}
.form-div {
    background-color: rgba(255, 255, 255, 0.27);
    border-radius: 10px;
    border: 1px solid #aaa;
    width: 424px;
    margin-top: 150px;
    margin-left:1050px;
    padding: 30px 0 20px 0px;
    font-size: 16px;
    box-shadow: inset 0px 0px 10px rgba(255, 255, 255, 0.5), 0px 0px 15px rgba(75, 75, 75, 0.3);
    text-align: left;
}
.form-div input[type="text"], .form-div input[type="password"], .form-div input[type="email"] {
    width: 268px;
    margin: 10px;
    line-height: 20px;
    font-size: 16px;
}
.form-div input[type="checkbox"] {
    margin: 20px 0 20px 10px;
}
.form-div input[type="button"], .form-div input[type="submit"] {
    margin: 10px 20px 0 0;
}
.form-div table {
    margin: 0 auto;
    text-align: right;
    color: rgba(64, 64, 64, 1.00);
}
.form-div table img {
    vertical-align: middle;
    margin: 0 0 5px 0;
}
.footer {
    color: rgba(64, 64, 64, 1.00);
    font-size: 12px;
    margin-top: 30px;
}
.form-div .buttons {
    float: right;
}
input[type="text"], input[type="password"], input[type="email"] {
    border-radius: 8px;
    box-shadow: inset 0 2px 5px #eee;
    padding: 10px;
    border: 1px solid #D4D4D4;
    color: #333333;
    margin-top: 5px;
}
input[type="text"]:focus, input[type="password"]:focus, input[type="email"]:focus {
    border: 1px solid #50afeb;
    outline: none;
}
input[type="button"], input[type="submit"] {
    padding: 7px 15px;
    background-color: #3c6db0;
    text-align: center;
    border-radius: 5px;
    overflow: hidden;
    min-width: 80px;
    border: none;
    color: #FFF;
    box-shadow: 1px 1px 1px rgba(75, 75, 75, 0.3);
}
input[type="button"]:hover, input[type="submit"]:hover {
    background-color: #5a88c8;
}
input[type="button"]:active, input[type="submit"]:active {
    background-color: #5a88c8;
}
.err_msg{
    color: red;
    padding-right: 170px;
}
#password_err,#tel_err{
    padding-right: 195px;
}
#reg_btn{
    margin-right:50px; width: 285px; height: 45px; margin-top:20px;
}
#checkCode{
    width: 100px;
}
#changeImg{
    color: aqua;
}

img

a.jpg

reg_bg_min.jpg

register.html

js部分

在这个js部分里面，一个点需要注意一下，就是这个responseText这个属性，这个属性接受的值首先是String类型，然后了，这个值就是访问的链接下对应的方法的返回值的对应的String类型格式。

<script>
    //1. 给用户名输入框绑定 失去焦点事件
    document.getElementById("username").onblur = function () {
        //2. 发送ajax请求
        // 获取用户名的值
        var username = this.value;
        console.log(username)
        // //2.1. 创建核心对象
        // var xhttp;
        // if (window.XMLHttpRequest) {
        //     xhttp = new XMLHttpRequest();
        // } else {
        //     // code for IE6, IE5
        //     xhttp = new ActiveXObject("Microsoft.XMLHTTP");
        // }
        // //2.2. 发送请求
        // xhttp.open("GET", "http://localhost:8080/selectUser?username="+username);
        // xhttp.send();
        //
        // //2.3. 获取响应
        // xhttp.onreadystatechange = function() {
        //     if (this.readyState == 4 && this.status == 200) {
        //         // alert(this.responseText);
        //         //判断
        //         if(this.responseText == "true"){
        //             //用户名存在，显示提示信息
        //             document.getElementById("username_err").style.display = '';
        //         }else {
        //             //用户名不存在 ，清楚提示信息
        //             document.getElementById("username_err").style.display = 'none';
        //         }
        //     }
        // };
        axios({
            method:"get",
            url:"http://localhost:8080/selectUser?username="+username,
            data:username
        }).then(function (resp){
            if (resp.data){
                //用户名存在，显示提示信息
                document.getElementById("username_err").style.display = '';
            } else {
                //用户名不存在 ，清楚提示信息
                document.getElementById("username_err").style.display = 'none';
            }
        })
    }
</script>

完整代码：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>欢迎注册</title>
    <link href="css/register.css" rel="stylesheet">
</head>
<body>
<div class="form-div">
    <div class="reg-content">
        <h1>欢迎注册</h1>
        <span>已有帐号？</span> <a href="login.html">登录</a>
    </div>
    <form id="reg-form" action="#" method="get">
        <table>
            <tr>
                <td>用户名</td>
                <td class="inputs">
                    <input name="username" type="text" id="username">
                    <br>
                    <span id="username_err" class="err_msg" style="display: none">用户名已存在</span>
                </td>
            </tr>
            <tr>
                <td>密码</td>
                <td class="inputs">
                    <input name="password" type="password" id="password">
                    <br>
                    <span id="password_err" class="err_msg" style="display: none">密码格式有误</span>
                </td>
            </tr>
            <tr>
                <td>验证码</td>
                <td class="inputs">
                    <input name="checkCode" type="text" id="checkCode">
                    <img src="imgs/a.jpg">
                    <a href="#" id="changeImg">看不清？</a>
                </td>
            </tr>
        </table>
        <div class="buttons">
            <input value="注 册" type="submit" id="reg_btn">
        </div>
        <br class="clear">
    </form>
</div>
<script src="js/axios-0.18.0.js"></script>
<script>
    //1. 给用户名输入框绑定 失去焦点事件
    document.getElementById("username").onblur = function () {
        //2. 发送ajax请求
        // 获取用户名的值
        var username = this.value;
        console.log(username)
        // //2.1. 创建核心对象
        // var xhttp;
        // if (window.XMLHttpRequest) {
        //     xhttp = new XMLHttpRequest();
        // } else {
        //     // code for IE6, IE5
        //     xhttp = new ActiveXObject("Microsoft.XMLHTTP");
        // }
        // //2.2. 发送请求
        // xhttp.open("GET", "http://localhost:8080/selectUser?username="+username);
        // xhttp.send();
        //
        // //2.3. 获取响应
        // xhttp.onreadystatechange = function() {
        //     if (this.readyState == 4 && this.status == 200) {
        //         // alert(this.responseText);
        //         //判断
        //         if(this.responseText == "true"){
        //             //用户名存在，显示提示信息
        //             document.getElementById("username_err").style.display = '';
        //         }else {
        //             //用户名不存在 ，清楚提示信息
        //             document.getElementById("username_err").style.display = 'none';
        //         }
        //     }
        // };
        axios({
            method:"get",
            url:"http://localhost:8080/selectUser?username="+username,
            data:username
        }).then(function (resp){
            if (resp.data){
                //用户名存在，显示提示信息
                document.getElementById("username_err").style.display = '';
            } else {
                //用户名不存在 ，清楚提示信息
                document.getElementById("username_err").style.display = 'none';
            }
        })
    }
</script>
</body>
</html>

效果展示：

如果输入的账户在失去焦点之后，发现这个用户没有在数据库中存在就不会发生啥。

如果存在的话就显示这个信息，已经存在了。

axios基本使用