本篇通过完整示例介绍如何实现一对多关系表单的相应服务及视图。
一、准备数据结构
示例所采用的数据结构为“物资需求”一对多“物资清单”，通过IDE的实体设计器如下所示：
1. 物资(DonateItem)
主键为Id(Guid)
2. 物资需求(Requirement)
主键为Id(Guid)
3. 物资清单(RequireItem)
主键为Req(Requirement)+Item(DonateItem)
添加实体成员时选择类型EntityRef（一对一）或EntitySet(一对多)可设置相应的导航属性
二、实现需求列表显示功能
1. 新建RequirementService服务实现加载列表数据
using System;
using System.Threading.Tasks;
namespace dns.ServiceLogic
{
public class RequirementService
{
/// <summary>
/// 分页加载需求记录
/// </summary>
public async Task<object> Load(int pageIndex, int pageSize)
{
var q = new SqlQuery<Entities.Requirement>();
q.Skip(pageSize * pageIndex).Take(pageSize);
q.OrderByDesc(t => t.Time);
return await q.ToListAsync();
}
}
}
2. 新建RequireList视图
2.1 模版
<div>
<el-button-group>
<el-button type="primary" icon="fas fa-plus-square fa-fw">新建</el-button>
<el-button type="primary" icon="fas fa-edit fa-fw">修改</el-button>
<el-button type="primary" icon="fas fa-trash fa-fw">删除</el-button>
<el-button @click="load" type="primary" icon="fas fa-search fa-fw">刷新</el-button>
</el-button-group>
<br/><br/>
<el-table :data="items" v-loading="loading" border stripe highlight-current-row
readonly>
<el-table-column prop="Donee" label="需求方"></el-table-column>
<el-table-column prop="Time" label="时间"></el-table-column>
<el-table-column prop="Contact" label="联系人"></el-table-column>
<el-table-column prop="Phone" label="电话"></el-table-column>
<el-table-column prop="Address" label="地址"></el-table-column>
<el-table-column prop="PostCode" label="邮编"></el-table-column>
</el-table>
<el-pagination background layout="prev, pager, next" :total="1000">
</el-pagination>
</div>
2.2 脚本
@Component
export default class RequireList extends Vue {
items = [] //需求列表
loading = false
pageIndex = 0
pageSize = 20
load() {
this.loading = true
dns.Services.RequirementService.Load(this.pageIndex, this.pageSize).then(res => {
this.$set(this, 'items', $runtime.parseEntity(res))
this.loading = false
}).catch(err => {
this.loading = false
this.$message.error('加载需求列表失败: ' + err)
})
}
mounted() {
this.load()
}
}
系统函数$runtime.parseEntity()用于将调用服务的结果内的数据对象如{ID:xxx,Name:xxx}转换为前端的Entity对象，另如果调用服务的结果只用作展示可以不用转换。
2.3 预览
点击“Preview”预览，当然当前没有任何数据。
三、实现新建需求功能
3.1 修改RequirementService实现保存方法
/// <summary>
/// 保存需求
/// </summary>
public async Task Save(Entities.Requirement req)
{
//TODO:验证
using var conn = await DataStore.Default.OpenConnectionAsync();
using var txn = conn.BeginTransaction();
//保存主记录
await DataStore.Default.SaveAsync(req, txn);
//保存子记录
foreach (var item in req.Items)
{
await DataStore.Default.SaveAsync(item, txn);
}
//处理已删除的物资
if (req.PersistentState != PersistentState.Detached)
{
foreach (var item in req.Items.DeletedItems)
{
await DataStore.Default.DeleteAsync(item, txn);
}
}
//递交事务
txn.Commit();
}
3.2 新建ItemService实现用于绑定的加载方法
using System;
using System.Threading.Tasks;
namespace dns.ServiceLogic
{
public class ItemService
{
/// <summary>
/// 加载用于前端选择绑定
/// </summary>
public async Task<object> LoadForSelect()
{
var q = new SqlQuery<Entities.DonateItem>();
return await q.ToListAsync(t => new { t.Id, t.Name, t.Spec });
}
}
}
3.3 新建RequireView编辑视图
3.3.1 模版
<div>
<!-- 表单头 -->
<el-row :gutter="20" type="flex">
<el-col :span="3">需求方:</el-col>
<el-col :span="9">
<el-input v-model="req.Donee"></el-input>
</el-col>
<el-col :span="3">时间:</el-col>
<el-col :span="9">
<el-date-picker v-model="req.Time" type="date" placeholder="选择日期">
</el-date-picker>
</el-col>
</el-row>
<br/>
<el-row :gutter="20" type="flex">
<el-col :span="3">联系人:</el-col>
<el-col :span="9">
<el-input v-model="req.Contact"></el-input>
</el-col>
<el-col :span="3">电话:</el-col>
<el-col :span="9">
<el-input v-model="req.Phone"></el-input>
</el-col>
</el-row>
<br/>
<el-row :gutter="20" type="flex">
<el-col :span="3">地址:</el-col>
<el-col :span="9">
<el-input v-model="req.Address"></el-input>
</el-col>
<el-col :span="3">邮编:</el-col>
<el-col :span="9">
<el-input v-model="req.PostCode"></el-input>
</el-col>
</el-row>
<br/>
<!-- 物资列表 -->
<el-table :data="items" border highlight-current-row readonly>
<el-table-column type="index"></el-table-column>
<el-table-column label="物资">
<template slot-scope="scope">
<el-select v-model="scope.row.ItemId" value-key="Id" placeholder="请选择">
<el-option v-for="item in optItems" :key="item.Id" :label="item.Name+' '+item.Spec"
:value="item.Id">
</el-option>
</el-select>
</template>
</el-table-column>
<el-table-column label="数量">
<template slot-scope="scope">
<el-input-number v-model="scope.row.Quantity" controls-position="right" :min="1">
</el-input-number>
</template>
</el-table-column>
<el-table-column label="备注">
<template slot-scope="scope">
<el-input v-model="scope.row.Comment"></el-input>
</template>
</el-table-column>
<el-table-column>
<template slot="header" slot-scope="scope">
<el-button @click="onAddItem" icon="fa fa-plus fa-fw" size="mini">添加</el-button>
</template>
<template slot-scope="scope">
<el-button @click="onDeleteItem(scope.$index)" icon="fa fa-times fa-fw" size="mini">删除</el-button>
</template>
</el-table-column>
</el-table>
<br/>
<div>
<el-button @click="onSave" type="primary" icon="fas fa-save fa-fw">保存</el-button>
</div>
</div>
3.3.2 脚本
@Component
export default class RequireView extends Vue {
@Prop({ type: Object, default: {} }) req: dns.Entities.Requirement
optItems = [] //物资选择列表
/** 用于Table绑定，过滤已标为删除的 */
get items() {
if (this.req.Items) {
return this.req.Items.filter(t => !t.isDeleted())
}
return null
}
/** 加载用于绑定下拉选择的物资列表 */
loadItems() {
dns.Services.ItemService.LoadForSelect().then(res => {
this.$set(this, 'optItems', res)
}).catch(err => {
this.$message.error("加载物资列表失败: " + err)
})
}
/** 添加物资 */
onAddItem() {
if (!this.req.Items) { //仅测试
this.$set(this.req, 'Items', [])
}
this.req.Items.push(new dns.Entities.RequireItem())
}
/** 删除物资 */
onDeleteItem(index) {
//新建的直接删除，旧的标为删除
if (this.req.Items[index].isNew()) {
this.req.Items.splice(index, 1)
} else {
this.req.Items[index].markDeleted()
}
}
onSave() {
dns.Services.RequirementService.Save(this.req).then(res => {
this.req.acceptChanges()
this.$message.success("保存成功")
}).catch(err => {
this.$message.error("保存错误: " + err)
})
}
mounted() {
this.loadItems()
}
}
3.4 修改RequireList视图，实现新建功能
3.4.1 模版
<el-button @click="onCreate" type="primary" icon="fas fa-plus-square fa-fw">新建</el-button>
<!-- 省略 -->
<el-dialog title="需求记录" :visible.sync="dlgVisible">
<require-view :req="current"></require-view>
</el-dialog>
<!-- 省略 -->
3.4.2 脚本
@Component({
components: { RequireView: dns.Views.RequireView }
})
export default class RequireList extends Vue {
//----省略----
dlgVisible = false
current = null
//----省略----
onCreate() {
this.current = new dns.Entities.Requirement()
this.dlgVisible = true
}
//----省略----
现在可以在预览内尝试添加些数据了！
四、实现需求列表Pop显示物资清单
