:data="" table中 v-bind:model="" :model="" form中 v-model指令的本质是:form-item中 1.它负责监听用户的输入事件,从而更新数据,并对一些极端场景进行一些特殊处理。 2.同时,v-model会忽略所有表单元素的value、checked、selected特性的初始值,它总是将vue实例中的数据作为数据来源。 3.然后当输入事件发生时,实时更新vue实例中的数据。 用v-bind和v-on指令实现v-model <input type="text" @input="handleInput($event)" placeholder="请输入" v-bind:value="message"> ========================================== map() 方法创建一个新数组,其结果是该数组中的每个元素都调用一个提供的函数后返回的结果。 var array1 = [1,4,9,16]; const map1 = array1.map(x => x *2); console.log(map1); Array [2,8,18,32] ========================================= el-table的数据源:data=, 单向绑定 vue + element UI <table>表格的常见的案例 https://www.jianshu.com/p/f1dd60cacfb5 ========================================== 由于JavaScript的限制,Vue 无法检测到对数组的以下更改: 1. 当你用索引直接设置一个项目,例如 vm.items[indexOfItem] = newValue 2. 当你修改数组的长度时,例如 vm.items.length = newLength 为了克服注意事项1 // Vue.set Vue.set(vm.items, indexOfItem, newValue) // Array.prototype.splice vm.items.splice(indexOfItem, 1, newValue) 为了克服注意事项2 vm.items.splice(newLength) ========================================== Vue不允许向已创建的实例动态添加新的根级别反应属性。但是,可以使用该Vue.set(object, key, value)方法为嵌套对象添加反应性属性。例如,给出: var vm = new Vue({ data: { userProfile: { name: 'Anika' } } }) 您可以使用以下方法将新age属性添加到嵌套userProfile对象: Vue.set(vm.userProfile, 'age', 27) 您也可以使用vm.$set实例方法,它是全局Vue.set的别名: this.$set(this.userProfile, 'age', 27) ========================================== 带有v-if的v-for 当它们存在于同一个节点上时,v-for其优先级高于v-if。这意味着v-if将分别在循环的每次迭代中运行。当您想要渲染仅用于某些项目的节点时,这非常有用,如下所示: <li v-for="todo in todos" v-if="!todo.isComplete"> {{ todo }} </li> 以上只会呈现不完整的待办事项。 ========================================== 需要注意的是,如果el-option是通过v-for指令渲染出来的,此时需要为el-option添加key属性,且其值需具有唯一性,比如此例中的item.value。 如果 Select 的绑定值为对象类型,请务必指定 value-key 作为它的唯一性标识。value / v-model 绑定值 ========================================== mounted() { this.list = this.states.map(item => { return { value: `value:${item}`, label: `label:${item}` }; }); }, ========================================== //------------------------公用方法定义-------------------// Vue.prototype.showMessage = function (name, type, msg) { var len = arguments.length; if (len == 3) { switch (arguments[0]) { case 'add': this.addAlertShow = true; this.addAlertMsg = arguments[2]; this.addAlertType = arguments[1]; break; case 'edit': this.editAlertShow = true; this.editAlertMsg = arguments[2]; this.editAlertType = arguments[1]; break; case 'maintain': this.maintainAlertShow = true; this.maintainAlertMsg = arguments[2]; this.maintainAlertType = arguments[1]; break; } } else if (len == 2) { if (arguments[0] == 'error') { this.$message.error(arguments[1]); } else if (arguments[0] == 'success') { this.$message({ showClose: true, message: arguments[1], type: 'success' }); } } } ============================================== html: v-loading="loading function getLBInfo() { this.loading = true; this.$http.post('/ToolingModelInfo/GetLBInfo',{ }, { emulateJSON: true } ).then(function (res) { if (res.data.ReturnResult == '0') { this.loading = false; this.showMessage('success', res.data.ReturnMessage); } else { this.loading = false; this.showMessage('error', res.data.ReturnMessage); } }, function () { this.loading = false; this.$message.error('查询数据失败!'); }); } vue: loadding : false =============================================== this.$nextTick()可以等待dom生成以后再来获取dom对象 this.$nextTick()在页面交互,尤其是从后台获取数据后重新生成dom对象之后的操作有很大的优势, this.$nextTick(() => { console.log(this.$refs['hello'].innerText); }); ================================================ el-form-item的嵌套 <el-form-item label="活动时间" required> <el-col :span="11"> <el-form-item prop="date1"> <el-date-picker type="date" placeholder="选择日期" v-model="ruleForm.date1" style=" 100%;"></el-date-picker> </el-form-item> </el-col> <el-col class="line" :span="2">-</el-col> <el-col :span="11"> <el-form-item prop="date2"> <el-time-picker placeholder="选择时间" v-model="ruleForm.date2" style=" 100%;"></el-time-picker> </el-form-item> </el-col> </el-form-item> prop 两个作用 ================================================ 都不选用change <el-form-item label="活动区域" prop="region"> <el-select v-model="ruleForm.region" placeholder="请选择活动区域"> <el-option label="区域一" value="shanghai"></el-option> <el-option label="区域二" value="beijing"></el-option> </el-select> </el-form-item> region: '', region: [ { required: true, message: '请选择活动区域', trigger: 'change' } ], date1: [ { type: 'date', required: true, message: '请选择日期', trigger: 'change' } ], resource: [ { required: true, message: '请选择活动资源', trigger: 'change' } ], ================================================== <el-form :model="ruleForm" status-icon :rules="rules" ref="ruleForm"> <el-button @click="resetForm('ruleForm')">重置</el-button> ================================================== 自定义验证 <el-form :model="ruleForm" status-icon :rules="rules" ref="ruleForm" label-width="100px" class="demo-ruleForm"> <el-form-item label="密码" prop="pass"> <el-input type="password" v-model="ruleForm.pass" autocomplete="off"></el-input> </el-form-item> <el-form-item label="确认密码" prop="checkPass"> <el-input type="password" v-model="ruleForm.checkPass" autocomplete="off"></el-input> </el-form-item> data() { var validatePass = (rule, value, callback) => { if (value === '') { callback(new Error('请输入密码')); } else { if (this.ruleForm.checkPass !== '') { this.$refs.ruleForm.validateField('checkPass'); } callback(); } }; var validatePass2 = (rule, value, callback) => { if (value === '') { callback(new Error('请再次输入密码')); } else if (value !== this.ruleForm.pass) { callback(new Error('两次输入密码不一致!')); } else { callback(); } }; rules: { pass: [ { validator: validatePass, trigger: 'blur' } ], ==================================================== <el-form :model="dynamicValidateForm" ref="dynamicValidateForm" label-width="100px" class="demo-dynamic"> <el-form-item prop="email" label="邮箱" :rules="[ { required: true, message: '请输入邮箱地址', trigger: 'blur' }, { type: 'email', message: '请输入正确的邮箱地址', trigger: ['blur', 'change'] } ]" > <el-input v-model="dynamicValidateForm.email"></el-input> </el-form-item> ================================================== 含有子表的添加删除 <el-form :model="dynamicValidateForm" ref="dynamicValidateForm" label-width="100px" class="demo-dynamic"> <el-form-item prop="email" label="邮箱" :rules="[ { required: true, message: '请输入邮箱地址', trigger: 'blur' }, { type: 'email', message: '请输入正确的邮箱地址', trigger: ['blur', 'change'] } ]" > <el-input v-model="dynamicValidateForm.email"></el-input> </el-form-item> <el-form-item v-for="(domain, index) in dynamicValidateForm.domains" :label="'域名' + index" :key="domain.key" :prop="'domains.' + index + '.value'" :rules="{ required: true, message: '域名不能为空', trigger: 'blur' }" > <el-input v-model="domain.value"></el-input><el-button @click.prevent="removeDomain(domain)">删除</el-button> </el-form-item> <el-form-item> <el-button type="primary" @click="submitForm('dynamicValidateForm')">提交</el-button> <el-button @click="addDomain">新增域名</el-button> <el-button @click="resetForm('dynamicValidateForm')">重置</el-button> </el-form-item> </el-form> <script> export default { data() { return { dynamicValidateForm: { domains: [{ value: '' }], email: '' } }; }, methods: { submitForm(formName) { this.$refs[formName].validate((valid) => { if (valid) { alert('submit!'); } else { console.log('error submit!!'); return false; } }); }, resetForm(formName) { this.$refs[formName].resetFields(); }, removeDomain(item) { var index = this.dynamicValidateForm.domains.indexOf(item) if (index !== -1) { this.dynamicValidateForm.domains.splice(index, 1) } }, addDomain() { this.dynamicValidateForm.domains.push({ value: '', key: Date.now() }); } } } </script> ======================================================= async type_change(type){ const d = await this.$http.post('/goods/api/get_goods',{type_id:type}) ======================================================= 在vue里,当你对一个不存在的属性或对象直接“.”进行赋值,或者对数组不存在的索引项直接用索引赋值, 从控制台打印可以看到数据变更,但无法使视图更新 ======================================================= forEach、for in 和for of的区别 forEach 不能使用break return 结束并退出循环 for in 和 for of 可以使用break return; for in遍历的是数组的索引(即键名),而for of遍历的是数组元素值。 for of遍历的只是数组内的元素,而不包括数组的原型属性method和索引name 所以 for in 更适合遍历对象,for of 适合遍历数组或者类数组