在数组中迭代数组时出错："Cannot find a differ supporting object '[object Object]' of type 'object'."

Question

我发现了一些类似的问题，但没有一个能帮助我解决这个问题。通过 Web API，我在终结点上提供了以下 json。

[
{
"counterparty": "JP X",
"callback": [
{
"contractId": 1,
"buy": true,
"instrument": "PET",
"tradeDate": "29/06/2020"
},
{   
"contractId": 2,
"buy": true,
"instrument": "PETW"
"tradeDate": "29/06/2020"
}]},
{
"counterparty": "JP",
"callback": [
{
"contractId": 12,
"buy": true,
"instrument": "PETR",
"tradeDate": "29/06/2020"
}]
}
]

我必须在ngx-datatable中组织这些数据，以便每行对应于counterparty字段，并且有一个ngx-datatable-row-detail，我可以在其中显示callback数组中的信息。使用服务连接到 webapi 后，我使用以下函数在 component.ts 中接收数据：

@Component({
selector: 'app-callback',
templateUrl: './callback-salesbonds.component.html',
styleUrls: ['./callback-salesbonds.component.scss']
})
export class CallbackSalesBondsComponent implements OnInit {
@ViewChild('tableWrapperList') tableWrapper;
@ViewChild('tableList') table: DatatableComponent;
currentComponentWidth;
operations: any;
constructor(private callbackService: CallbackService, 
private ref: ChangeDetectorRef,     
private fb: FormBuilder) 
{ 
this.filter = fb.group({
tradeDate: new FormControl(new Date())      
});
}
public getOperations = () => {
var operations = this.callbackService
.SendDate(this.filter.get('tradeDate').value)
.subscribe(source => this.operations = source);          
}
ngAfterContentChecked(){
if (this.table && this.table.recalculate && (this.tableWrapper.nativeElement.clientWidth !== this.currentComponentWidth)) {
setTimeout(() => {         
this.currentComponentWidth = this.tableWrapper.nativeElement.clientWidth;
this.table.recalculate();
this.ref.detectChanges();
window.dispatchEvent(new Event('resize'));
}, 300);
}
}
toggleExpandRow(row) {
this.table.rowDetail.toggleExpandRow(row);
}

我的.html组件如下所示：

<pg-container>
<div class="row">
<div class="table table-responsive mt-0">
<div class="bg-black table-responsive collapse-border" #tableWrapperList
ng>
<ngx-datatable #tableList 
[columnMode]="'flex'"
[rows]="operations"
<ngx-datatable-row-detail [rowHeight]="150" #myDetailRow>
<ng-template let-row="row" let-expanded="expanded" ngx-datatable-row-detail-template>
<table  class="table table-inline m-l-40 m-r-40 m-t-10">
<tr *ngFor="let r of row">
<td class="row-detail-td-title">contractId</td>
<td class="row-detail-td">{{r.callback.contractId}}</td>
</tr>
<tr *ngFor="let r of row">
<td class="row-detail-td-title">Buy</td>
<td class="row-detail-td">{{r.callback.buy}}</td>
</tr>
<tr *ngFor="let r of row">
<td class="row-detail-td-title">Instrument</td>
<td class="row-detail-td">{{r.callback.instrument}}</td>
</tr>
</table>
</ng-template>
</ngx-datatable-row-detail>


<ngx-datatable-column [flexGrow]=5 name="Contraparte" prop="counterparty" cellClass="d-flex align-items-center text-center" headerClass="text-center">
<ng-template let-value="value" ngx-datatable-cell-template>
{{value}}
</ng-template>
</ngx-datatable-column>

<ngx-datatable-column [flexGrow]="0.5" [sortable]="false" cellClass="d-flex align-items-center text-center">
<ng-template let-row="row" let-expanded="expanded" ngx-datatable-cell-template>
<a
href="javascript:void(0)"
[ngClass]="expanded ? 'fa fa-search-minus' : 'fa fa-search-plus'"
title="Expand/Collapse Row"
(click)="toggleExpandRow(row)"
>
</a>
</ng-template>
</ngx-datatable-column>
</ngx-datatable>
</div> 
</div>
</div>
</pg-container>

我可以将counterparty字段带到表中，但是当我单击以获取每个交易对手callback中的数据时，我犯了以下错误：

错误

错误：找不到不同的支持对象"[对象对象]" 类型为"对象"。NgFor 仅支持绑定到可迭代对象，例如 阵 列。 在NgForOf.push../node_modules/@angular/common/fesm5/common.js.NgForOf.ngOnChanges

谁能告诉我哪里出错了？

Answer 1

我找到了解决方案，只需使用 ngFor 迭代回调数组：

<ngx-datatable-row-detail [rowHeight]="150" #myDetailRow>
<ng-template let-row="row" let-expanded="expanded" ngx-datatable-row-detail-template>
<table  class="table table-inline m-l-40 m-r-40 m-t-10"  *ngFor="let r of row.callback">
<tr>
<td class="row-detail-td-title">contractId</td>
<td class="row-detail-td">{{r.contractId}}</td>
</tr>
<tr>
<td class="row-detail-td-title">Buy</td>
<td class="row-detail-td">{{r.buy}}</td>
</tr>
<tr>
<td class="row-detail-td-title">Instrument</td>
<td class="row-detail-td">{{r.instrument}}</td>
</tr>
</table>
</ng-template>
</ngx-datatable-row-detail>