How to Iterate Using Ngfor Loop Map Containing Key as String and Values as Map Iteration

How to iterate using ngFor loop Map containing key as string and values as map iteration

For Angular 6.1+ , you can use default pipe keyvalue ( Do review and upvote also ) :

<ul>
    <li *ngFor="let recipient of map | keyvalue">
        {{recipient.key}} --> {{recipient.value}}
    </li>
</ul>

WORKING DEMO

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For the previous version :

One simple solution to this is convert map to array : Array.from

Component Side :

map = new Map<String, String>();

constructor(){
    this.map.set("sss","sss");
    this.map.set("aaa","sss");
    this.map.set("sass","sss");
    this.map.set("xxx","sss");
    this.map.set("ss","sss");
    this.map.forEach((value: string, key: string) => {
        console.log(key, value);
    });
}

getKeys(map){
    return Array.from(map.keys());
}

Template Side :

<ul>
  <li *ngFor="let recipient of getKeys(map)">
    {{recipient}}
   </li>
</ul>

WORKING DEMO

Angular ngFor using a Map

if you only need the values, you can iterate over those

html:

<ion-item ion-item *ngFor="let item of getValues()">
    <h2>{{ item.time }}</h2>
</ion-item>

ts:

getValues(): Array<IShared_Position> {
    return Array.from(this.shared_position.values());
}

if you need both values, you can convert the Map to an iterateable object containing arrays with the key at index 0 and value at index 1 using the entries-function:

html:

<ion-item ion-item *ngFor="let item of getEntries()">
    <h2>key: {{ item[0] }} - time: {{item[1].time}}</h2>
</ion-item>

ts:

getEntries(): [string, IShared_Position] {
    return Array.from(this.shared_position.entries());
}

access key and value of object using *ngFor

As in latest release of Angular (v6.1.0) , Angular Team has added new built in pipe for the same named as keyvalue pipe to help you iterate through objects, maps, and arrays, in the common module of angular package.
For example -

<div *ngFor="let item of testObject | keyvalue">
    Key: <b>{{item.key}}</b> and Value: <b>{{item.value}}</b>
</div>

To keep original order, use keyvalue:onCompare,

and in component define callback:

// ...
import {KeyValue} from '@angular/common';

@Component(/* ... */)
export class MyComponent {
  private onCompare(_left: KeyValue<any, any>, _right: KeyValue<any, any>): number {
    return -1;
  }
}

Working Forked Example

check it out here for more useful information -

• https://github.com/angular/angular/blob/master/CHANGELOG.md#features-3
• https://github.com/angular/angular/commit/2b49bf7

If you are using Angular v5 or below or you want to achieve using pipe follow this answer

• access key and value of object using ngfor

Iterating 2 elements in a *ngfor iteration of custom interface array in angular

You mean memberInfo[i+1] instead of info[I+1].

As the error says, info is an object of type MemberInfo, it's not an array.

Note that you'll have to handle duplicate items with your current solution. There are many ways to handle it (code, CSS...) but this is out of scope of this question.

How to iterate object keys using *ngFor

Angular 6.0.0

https://github.com/angular/angular/blob/master/CHANGELOG.md#610-2018-07-25

introduced a KeyValuePipe

See also https://angular.io/api/common/KeyValuePipe

@Component({
  selector: 'keyvalue-pipe',
  template: `<span>
    <p>Object</p>
    <div *ngFor="let item of object | keyvalue">
      {{item.key}}:{{item.value}}
    </div>
    <p>Map</p>
    <div *ngFor="let item of map | keyvalue">
      {{item.key}}:{{item.value}}
    </div>
  </span>`
})
export class KeyValuePipeComponent {
  object: {[key: number]: string} = {2: 'foo', 1: 'bar'};
  map = new Map([[2, 'foo'], [1, 'bar']]);
}

original

You can use a pipe

@Pipe({ name: 'keys',  pure: false })
export class KeysPipe implements PipeTransform {
    transform(value: any, args: any[] = null): any {
        return Object.keys(value)//.map(key => value[key]);
    }
}

<div *ngFor="let key of objs | keys">

See also How to iterate object keys using *ngFor?

Iterating through a List<Map<String, Object>> map in Thymeleaf

You have to iterate list first, and then read each map from list & then read map object with the help of key like this:

Java Code:

List<Map<String, String>> mapList = new ArrayList<>();

Map<String, Object> firstMap = new HashMap<>();
firstMap.put("id", "1");
firstMap.put("name", "test_name_1");

Map<String, Object> secondMap = new HashMap<>();
secondMap.put("id", "2");
secondMap.put("name", "test_name_2");

mapList.add(firstMap);
mapList.add(secondMap);

model.put("map_list", mapList);

Thymeleaf Code:

<tr th:each="map : ${map_list}">
<td> CNP:</td>
<td th:text ="${map.get('id')}" ></td>
<td> Nume:</td>
<td th:text ="${map.get('name')}" ></td>
</tr>

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