vue实战——登录【详解】(含自适配全屏背景，记住账号--支持多账号，显隐密码切换，登录状态保持）

效果预览

在这里插入图片描述

技术要点——自适配全屏背景

https://blog.csdn.net/weixin_41192489/article/details/119992992

技术要点——密码输入框

自定义图标切换显示隐藏
https://blog.csdn.net/weixin_41192489/article/details/133940676

技术要点——记住账号（支持多账号）

核心需求和逻辑

勾选“记住账号”，一旦登录成功过，下次登录能在账号输入框的输入推荐建议列表中，选择该账号

在这里插入图片描述

未勾选“记住账号”，登录成功后，清除对该账号的存储

相关代码

页面加载时，获取记住的账号

  mounted() {
    this.accountList = JSON.parse(localStorage.getItem("accountList")) || [];
  },

使用带输入建议的输入框

          <el-autocomplete
            clearable
            class="inputStyle"
            v-model="formData.account"
            :fetch-suggestions="queryAccount"
            placeholder="请输入账号"
            @select="chooseAccount"
          ></el-autocomplete>

根据输入内容，从记住的账号中，过滤出最接近的已记住的账号

    queryAccount(queryString, cb) {
      let accountList = JSON.parse(JSON.stringify(this.accountList));
      accountList = accountList.map((item) => {
        return {
          value: item,
        };
      });

      var results = queryString
        ? accountList.filter(this.createFilter(queryString))
        : accountList;

      cb(results);
    },

    createFilter(queryString) {
      return (restaurant) => {
        return (
          restaurant.value.toLowerCase().indexOf(queryString.toLowerCase()) ===
          0
        );
      };
    },

根据输入建议下拉选择中，选择已记住的账号时，自动勾选记住账号，并清空表单校验

    chooseAccount(newAccount) {
      if (this.accountList.includes(newAccount.value)) {
        this.remember = true;
      }
      this.$nextTick(() => {
        this.$refs.formRef.clearValidate();
      });
    },

登录成功后，根据是否勾选记住账号，存入新账号或移除已记住的账号。

                this.$message({
                  offset: 150,
                  message: "登录成功！",
                  type: "success",
                });

                let account = this.formData.account;

                // 勾选-记住账号
                if (this.remember) {
                  // 没记住过
                  if (!this.accountList.includes(account)) {
                    // 存入localStorage
                    this.accountList.push(account);
                    localStorage.setItem(
                      "accountList",
                      JSON.stringify(this.accountList)
                    );
                  }
                } else {
                  // 未勾选-记住账号
                  removeItem(this.accountList, account);
                  localStorage.setItem(
                    "accountList",
                    JSON.stringify(this.accountList)
                  );
                }

用到的工具函数

// 普通数组移除指定元素
function removeItem(arr, item) {
  let targetIndex = arr.findIndex((itemTemp) => itemTemp === item);
  if (targetIndex !== -1) {
    arr.splice(targetIndex, 1);
  }
}

技术要点——登录后维持登录状态

this.$store.commit("set_token", res.data.data.token);
this.$store.commit("set_isLogin", true);
this.$store.commit("set_userInfo", res.data.data);

完整范例代码

<template>
  <div class="bg loginPage">
    <div>
      <div>
        <div class="hello">Hi，你好！</div>
        <div class="hello2">欢迎进入观光车调度系统</div>
      </div>
      <div class="logoBox">
        <img
          class="logoBox"
          src="@/assets/images/login/login_logo.png"
          alt=""
        />
      </div>
    </div>

    <div class="loginBox">
      <div class="welcomeLogin">欢迎登录</div>
      <el-form ref="formRef" :model="formData" label-width="0px">
        <el-form-item
          prop="account"
          :rules="{ required: true, message: '请输入账号' }"
        >
          <div class="formLabel">账号</div>
          <el-autocomplete
            clearable
            class="inputStyle"
            v-model="formData.account"
            :fetch-suggestions="queryAccount"
            placeholder="请输入账号"
            @select="chooseAccount"
          ></el-autocomplete>
        </el-form-item>
        <el-form-item
          prop="password"
          :rules="{ required: true, message: '请输入密码' }"
        >
          <div class="formLabel">密码</div>
          <el-input
            placeholder="密码"
            v-model="formData.password"
            :type="showPassword ? 'text' : 'password'"
          >
            <i slot="suffix" @click="switchPassword">
              <img
                v-if="showPassword"
                class="input_icon"
                src="@/assets/icons/password_show.png"
              />
              <img
                v-else
                class="input_icon"
                src="@/assets/icons/password_hide.png"
              />
            </i>
          </el-input>
        </el-form-item>
      </el-form>

      <el-checkbox v-model="remember">记住账号</el-checkbox>

      <el-button class="loginBtn" type="primary" @click="login"
        >立即登录</el-button
      >
    </div>
  </div>
</template>

<script>
import { api_login } from "@/APIs/login.js";

export default {
  data() {
    return {
      accountList: [],
      remember: false,
      // 是否显示密码
      showPassword: false,
      formData: {},
    };
  },
  mounted() {
    this.accountList = JSON.parse(localStorage.getItem("accountList")) || [];
  },
  methods: {
    chooseAccount(newAccount) {
      if (this.accountList.includes(newAccount.value)) {
        this.remember = true;
      }
      this.$nextTick(() => {
        this.$refs.formRef.clearValidate();
      });
    },
    queryAccount(queryString, cb) {
      let accountList = JSON.parse(JSON.stringify(this.accountList));
      accountList = accountList.map((item) => {
        return {
          value: item,
        };
      });

      var results = queryString
        ? accountList.filter(this.createFilter(queryString))
        : accountList;

      cb(results);
    },

    createFilter(queryString) {
      return (restaurant) => {
        return (
          restaurant.value.toLowerCase().indexOf(queryString.toLowerCase()) ===
          0
        );
      };
    },
    switchPassword() {
      this.showPassword = !this.showPassword;
    },

    gotoIndex() {
      this.$router.push("/");
    },

    login() {
      this.$refs.formRef.validate((valid) => {
        if (valid) {
          this.loading = this.$loading({
            text: "登录中",
            spinner: "el-icon-loading",
            background: "rgba(0, 0, 0, 0.7)",
            lock: true,
          });

          api_login({
            ...this.formData,
          })
            .then((res) => {
              if (res.data.code === 200) {
                this.$store.commit("set_token", res.data.data.token);
                this.$store.commit("set_isLogin", true);
                delete res.data.data["token"];
                this.$store.commit("set_userInfo", res.data.data);

                this.$message({
                  offset: 150,
                  message: "登录成功！",
                  type: "success",
                });

                let account = this.formData.account;

                // 勾选-记住账号
                if (this.remember) {
                  // 没记住过
                  if (!this.accountList.includes(account)) {
                    // 存入localStorage
                    this.accountList.push(account);
                    localStorage.setItem(
                      "accountList",
                      JSON.stringify(this.accountList)
                    );
                  }
                } else {
                  // 未勾选-记住账号
                  removeItem(this.accountList, account);
                  localStorage.setItem(
                    "accountList",
                    JSON.stringify(this.accountList)
                  );
                }

                this.gotoIndex();
              } else {
                this.$message({
                  offset: 150,
                  message: res.data.msg,
                  type: "warning",
                });
              }
              this.loading.close();
            })
            .catch(() => {
              this.loading.close();
            });
        }
      });
    },
  },
};

// 普通数组移除指定元素
function removeItem(arr, item) {
  let targetIndex = arr.findIndex((itemTemp) => itemTemp === item);
  if (targetIndex !== -1) {
    arr.splice(targetIndex, 1);
  }
}
</script>

<style scoped>
.input_icon {
  cursor: pointer;
  width: 24px;
  padding-top: 8px;
  padding-right: 6px;
}

.bg {
  background-image: url("~@/assets/images/login/login_bg.png");
  background-size: 100% 100%;
  position: fixed;
  top: 0px;
  width: 100%;
  height: 100%;
}

.loginBox {
  width: 390px;
  height: 492px;
  background: #ffffff;
  padding: 40px;
  box-sizing: border-box;
}
.loginPage {
  display: flex;
  justify-content: space-around;
  align-items: center;
  padding: 0px 90px;
  box-sizing: border-box;
}
.logoBox {
  width: 439px;
  height: 341px;
}
.hello {
  height: 63px;
  font-size: 45px;
  font-family: PingFangSC, PingFang SC;
  font-weight: 600;
  color: #ffffff;
  line-height: 63px;
}
.hello2 {
  height: 44px;
  font-size: 32px;
  font-family: PingFangSC, PingFang SC;
  font-weight: 600;
  color: #ffffff;
  line-height: 44px;
  margin-bottom: 46px;
  margin-top: 12px;
}
.welcomeLogin {
  height: 25px;
  font-size: 18px;
  font-family: PingFangSC, PingFang SC;
  font-weight: 600;
  color: #2b2d31;
  line-height: 25px;
  text-align: center;
  margin-bottom: 26px;
}
.formLabel {
  margin-top: 20px;
  height: 21px;
  font-size: 15px;
  font-family: PingFangSC, PingFang SC;
  font-weight: 400;
  color: #2b2d31;
  line-height: 21px;
  margin-bottom: 10px;
}

.loginBtn {
  height: 51px;
  background: #3e6ff6;
  border-radius: 6px;
  width: 100%;
  margin-top: 50px;
}
.inputStyle {
  width: 100%;
}
</style>