Convert complex JSON to flat JSON in Angular Pivotview component
23 Aug 202522 minutes to read
Overview
The Angular Pivotview component requires data in flat JSON format for proper binding. This guide explains how to convert complex, nested JSON structures to flat JSON format and bind it to the pivot table.
Understanding complex vs flat JSON
Complex JSON contains nested objects and arrays, making it difficult to directly bind to the pivot table. For example:
{
"CustomerID": "VINET",
"Freight": 32.38,
"OrderDetails": [
{
"OrderID": 10248,
"OrderDate": "1996-07-04T10:10:00.000Z"
}
],
"ShipDetails": [
{
"ShipName": "Vins et alcools Chevalier",
"ShipAddress": "59 rue de l'Abbaye",
"ShipCity": "Reims",
"ShipRegion": null,
"ShipCountry": "France",
"ShippedDate": "1996-07-16T12:20:00.000Z"
}
]
}Flat JSON has a simple key-value structure without nesting, which is suitable for pivot table binding:
{
"CustomerID": "VINET",
"Freight": 32.38,
"OrderID": 10248,
"OrderDate": "1996-07-04T10:10:00.000Z",
"ShipName": "Vins et alcools Chevalier",
"ShipAddress": "59 rue de l'Abbaye",
"ShipCity": "Reims",
"ShipRegion": null,
"ShipCountry": "France",
"ShippedDate": "1996-07-16T12:20:00.000Z"
}Implementation
You can convert complex JSON to flat JSON programmatically and bind it to the pivot table using the dataSource property in the load event.
In the following example, the complexToFlatJson() method is used to convert complex JSON to flat JSON and bind it to the pivot table using the dataSource property, then modifying the field names in the rows and columns based on the converted flat JSON under dataSourceSettings in the load event.
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { PivotViewAllModule, PivotFieldListAllModule } from '@syncfusion/ej2-angular-pivotview'
import { Component, ViewChild, OnInit } from '@angular/core';
import {
PivotView, FieldListService, LoadEventArgs
} from '@syncfusion/ej2-angular-pivotview';;
import { enableRipple } from '@syncfusion/ej2-base';
import { DataSourceSettingsModel } from '@syncfusion/ej2-pivotview/src/model/datasourcesettings-model';
enableRipple(false);
let parentProp: any = {};
let dataSource: Object[][];
@Component({
imports: [
PivotViewAllModule,
PivotFieldListAllModule
],
standalone: true,
selector: 'app-container',
providers: [FieldListService],
// specifies the template string for the pivot table component
template: `<ejs-pivotview #pivotview id='PivotView' [dataSourceSettings]=dataSourceSettings
showFieldList='true' width='100%' height='350' showFieldList='true' (load)='load($event)'
showToolbar='true'></ejs-pivotview>`
})
export class AppComponent implements OnInit {
public dataSourceSettings?: DataSourceSettingsModel;
@ViewChild('pivotview', { static: false })
public pivotGridObj?: PivotView;
load(args: LoadEventArgs | any) {
dataSource = JSON.parse(JSON.stringify(args.dataSourceSettings.dataSource));
args.dataSourceSettings.dataSource = this.complexToFlatJson(dataSource);
let rows: any = [];
for (let i: number = 0; i < args.dataSourceSettings.rows.length; i++) {
if (args.dataSourceSettings.rows[i].name in parentProp) {
rows = rows.concat(parentProp[args.dataSourceSettings.rows[i].name]);
} else {
rows.push(args.dataSourceSettings.rows[i]);
}
}
args.dataSourceSettings.rows = rows;
let columns: any = [];
for (let i: number = 0; i < args.dataSourceSettings.columns.length; i++) {
if (args.dataSourceSettings.columns[i].name in parentProp) {
columns = columns.concat(
parentProp[args.dataSourceSettings.columns[i].name]
);
} else {
columns.push(args.dataSourceSettings.columns[i]);
}
}
args.dataSourceSettings.columns = columns;
}
complexToFlatJson(data: Object[][]) {
let flatArray: any = [];
let flatObject: any = {};
for (let index = 0; index < data.length; index++) {
for (let prop in data[index]) {
let value: Object = data[index][prop];
if (Array.isArray(value)) {
for (let i: number = 0; i < value.length; i++) {
let childProp: any = [];
for (let inProp in value[i]) {
flatObject[inProp] = value[i][inProp];
let object = {
name: inProp,
};
childProp.push(object);
}
parentProp[prop] = childProp;
}
} else {
flatObject[prop] = value;
}
}
flatArray.push(flatObject);
flatObject = {};
}
return flatArray;
}
data() {
return [
{
CustomerID: 'VINET',
Freight: 32.38,
OrderDetails: [
{
OrderID: 10248,
OrderDate: '1996-07-04T10:10:00.000Z',
}
],
ShipDetails: [
{
ShipName: 'Vins et alcools Chevalier',
ShipAddress: "59 rue de l'Abbaye",
ShipCity: 'Reims',
ShipRegion: null,
ShipCountry: 'France',
ShippedDate: '1996-07-16T12:20:00.000Z',
}
]
},
{
CustomerID: 'GALED',
Freight: 10.14,
OrderDetails: [
{
OrderID: 10366,
OrderDate: '1996-11-28T00:00:00.000Z',
}
],
ShipDetails: [
{
ShippedDate: '1996-12-30T00:00:00.000Z',
ShipName: 'Galería del gastronómo',
ShipAddress: 'Rambla de Cataluña, 23',
ShipCity: 'Barcelona',
ShipRegion: null,
ShipCountry: 'Spain',
}
]
},
{
CustomerID: 'VAFFE',
Freight: 13.55,
OrderDetails: [
{
OrderID: 10367,
OrderDate: '1996-12-02T00:00:00.000Z',
}
],
ShipDetails: [
{
ShippedDate: '1996-12-30T00:00:00.000Z',
ShipName: 'Vaffeljernet',
ShipAddress: 'Smagsloget 45',
ShipCity: 'Århus',
ShipRegion: null,
ShipCountry: 'Denmark',
}
]
},
{
CustomerID: 'ERNSH',
Freight: 101.95,
OrderDetails: [
{
OrderID: 10368,
OrderDate: '1996-11-29T00:00:00.000Z',
}
],
ShipDetails: [
{
ShippedDate: '1996-12-30T00:00:00.000Z',
ShipName: 'Ernst Handel',
ShipAddress: 'Kirchgasse 6',
ShipCity: 'Graz',
ShipRegion: null,
ShipCountry: 'Austria',
}
]
},
{
CustomerID: 'SPLIR',
Freight: 195.68,
OrderDetails: [
{
OrderID: 10369,
OrderDate: '1996-11-28T00:00:00.000Z',
}
],
ShipDetails: [
{
ShippedDate: '1996-12-30T00:00:00.000Z',
ShipName: 'Split Rail Beer & Ale',
ShipAddress: 'P.O. Box 555',
ShipCity: 'Lander',
ShipRegion: 'WY',
ShipCountry: 'USA',
},
]
}
];
}
ngOnInit(): void {
this.dataSourceSettings = {
expandAll: true,
enableSorting: true,
dataSource: this.data() as any,
columns: [{ name: 'OrderDetails' }],
values: [{ name: 'Freight', caption: 'Units Sold' }],
rows: [{ name: 'ShipDetails' }],
valueSortSettings: { headerDelimiter: ' - ' },
formatSettings: [{ name: 'Amount', format: 'C0' }]
};
}
}import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));