response.json return problem - undefinied

Question

I have got problem with response . json() return problem. I have got two methods one is Mocking List, and another is by JSON. Mock method works superb. but return from response.json() returned me undefined values.

The records are the same like in list - 4, but for all columns it returned undefined.

Here is my code:

private _getMockListData(): Promise<ISPLists> {
    return MockHttpList.get(this.context.pageContext.web.absoluteUrl).then(() => {
            const listData: ISPLists = {
                value:
                [
                    { Tytuł1: 'WP', Link1: 'www.wp.pl', Link_zdjecie1: 'https://d.wpimg.pl/10002867-366860448/392x330.png'},
                    { Tytuł1: 'Onet', Link1: 'www.onet.pl', Link_zdjecie1: 'https://upload.wikimedia.org/wikipedia/commons/b/b7/Onet_pl.png'},
                    { Tytuł1: 'Interia', Link1: 'www.interia.pl', Link_zdjecie1: 'https://upload.wikimedia.org/wikipedia/commons/b/b7/Onet_pl.png'}
                ]
            };
            return listData;
        }
    ) as Promise<ISPLists>;
}

private async _getListData(): Promise<ISPLists> {
    return this.context.spHttpClient.get('https://sharepointTenant/sites/SharepointSite/_api/web/lists/GetByTitle(\'Wlasciwosci_toolbox\')/Items', SPHttpClient.configurations.v1)
    .then((response: SPHttpClientResponse) => {
        return response.json();
    });
}

Please help me. Here is two code errors:

Answer 1

Try using below code:

private _getListData(): Promise<ISPLists> {  
    return this.context.spHttpClient.get(this.context.pageContext.web.absoluteUrl + `/_api/web/lists/GetByTitle('Display Name of List')/Items`, SPHttpClient.configurations.v1)  
        .then((response: SPHttpClientResponse) => {   
            debugger;  
            return response.json();  
    });  
}

Replace Display Name of List in code with the Display name of your list.

Answer 2

I did sample test project and shared in github, hope this would help you.

this.props.context.spHttpClient.get(`${this.props.context.pageContext.web.absoluteUrl}/_api/web/lists/getbytitle('TestList')/items?select=ID,Title,Address`,
    SPHttpClient.configurations.v1) .then((response: SPHttpClientResponse) => {  
      response.json().then((responseJSON: any) => {            
        reactHandler.setState({
          items: responseJSON.value
        });
      });  
    }); 

https://github.com/OS-Lee/ReactSPFx/blob/master/src/webparts/reactSpFx/components/ReactSpFx.tsx