AppBox实战: 如何实现一对多表单的增删改查

  本篇经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。

1、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”，经过IDE的实体设计器以下所示：

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

2、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" width="80"></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" width="80"></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，另若是调用服务的结果只用做展现能够不用转换。

2.3 预览

  点击“Preview”预览，固然当前没有任何数据。

3、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" align="middle">
        <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" style="width:100%">
            </el-date-picker>
        </el-col>
    </el-row>
    <br/>
    <el-row :gutter="20" type="flex" align="middle">
        <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" align="middle">
        <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" width="280px">
            <template slot-scope="scope">
                <el-select v-model="scope.row.ItemId" value-key="Id" style="width:100%" 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" width="130px">
            <template slot-scope="scope">
                <el-input-number v-model="scope.row.Quantity" controls-position="right" :min="1" style="width:100%">
                </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 align="right" width="100px">
            <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 style="text-align:center">
        <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" width="800px">
        <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----

如今能够在预览内尝试添加些数据了！

4、实现需求列表Pop显示物资清单

  主列表使用懒加载方式加载子表数据。

4.1 修改RequirementService服务实现加载子表数据方法

/// <summary>
/// 加载需求物资列表
/// </summary>
public async Task<object> LoadItems(Guid reqId)
{
    var q = new SqlQuery<Entities.RequireItem>();
    q.Where(t => t.ReqId == reqId);
    q.Include(t => t.Item.Name);
    q.Include(t => t.Item.Spec);
    return await q.ToListAsync();
}

4.2 修改RequireList视图

4.2.1 模版

<!-- 省略 -->
<el-table-column label="需求物资" width="80">
    <template slot-scope="scope">
        <!-- 物资清单列表 -->
        <el-popover @show="loadItems(scope.row)" trigger="hover" placement="left" width="400">
            <el-row v-for="(item,index) in scope.row.Items" :gutter="20">
                <el-col :span="2">{{index+1}}.</el-col>
                <el-col :span="4">{{item.ItemName}}</el-col>
                <el-col :span="14">{{item.ItemSpec}}</el-col>
                <el-col :span="4">{{item.Quantity}}</el-col>
            </el-row>
            <div slot="reference">
                <el-tag size="medium">物资清单</el-tag>
            </div>
        </el-popover>
    </template>
</el-table-column>
<!-- 省略 -->

4.2.2 脚本

/** 加载需求物资清单 */
loadItems(row: dns.Entities.Requirement) {
    if (row.Items) { return }
    dns.Services.RequirementService.LoadItems(row.Id).then(res => {
        this.$set(row, 'Items', $runtime.parseEntity(res))
    }).catch(err => {
        this.$message.error('加载物资列表失败: ' + err)
    })
}

4.2.3 预览

5、实现修改与删除功能

5.1 修改RequirementService服务实现删除方法

public async Task Delete(Entities.Requirement req)
{
    //TODO:判断状态，已发放物资的不能删除
    using var conn = await DataStore.Default.OpenConnectionAsync();
    using var txn = conn.BeginTransaction();
    //先删除子表记录
    var deleteItems = new SqlDeleteCommand<Entities.RequireItem>();
    deleteItems.Where(t => t.ReqId == req.Id);
    await DataStore.Default.ExecCommandAsync(deleteItems, txn);
    //再删除主表记录
    await DataStore.Default.DeleteAsync(req, txn);
    //递交事务
    txn.Commit();
}

5.2 修改RequireList视图

5.2.1 模版

<!-- 省略 -->
<el-button @click="onEdit" type="primary" icon="fas fa-edit fa-fw">修改</el-button>
<el-button @click="onDelete" type="primary" icon="fas fa-trash fa-fw">删除</el-button>
<!-- 省略 -->
<el-table :data="items" v-loading="loading" @current-change="onCurrentChanged" border stripe highlight-current-row
        readonly>

5.2.2 脚本

//----省略----
export default class RequireList extends Vue {
    //----省略----
    currentRow = null
    //----省略----
    onCurrentChanged(row) {
        this.currentRow = row
    }
    onEdit() { 
        if (!this.currentRow) {
            this.$message.warning("请先选择记录")
            return
        }
        this.loadItems(this.currentRow)
        this.current = this.currentRow
        this.dlgVisible = true
    }
    onDelete() {
        if (!this.currentRow) {
            this.$message.warning("请先选择记录")
            return
        }
        this.$confirm('确认删除选择的记录吗?', '提示', {
            confirmButtonText: '肯定',
            cancelButtonText: '取消',
            type: 'warning'
        }).then(() => {
            dns.Services.RequirementService.Delete(this.currentRow).then(res => {
                this.$message.success("删除成功");
            }).catch(err => {
                this.$message.error("删除失败: " + err)
            })
        }).catch(() => { })
    }
    //----省略----

5.2.3 预览

6、本篇小结

  做者上篇提到实现独立的不依赖内置存储的版本，本篇示例便是基于此版本，下一步重点是针对此版本的测试与Bug修复。另外一边码代码一边码文实属不易，做者须要您的支持请您多多点赞推荐！