獲取 SPFx web 零件的數據？ 即使它是 output 到控制台，也沒有數據返回

Question

我正在為 SharePoint Online 創建一個 SPFx webpart。 我使用此代碼。 它確實將值寫入控制台（組中人員的所有 email 地址），但不會返回“stringToReturn”值以顯示在 web 部分中。

我的 web 零件顯示：會見團隊... undefined

我在做一些根本錯誤的事情嗎？

謝謝P

public async render(): Promise<void> {

    
      this.domElement.innerHTML = `
      <section>
        <div>
          Meet the Team...
        </div>
        
        <div>
        ${await this.getGroupData()}
        </div>
      </section>`;
    }

protected async getGroupData(): Promise<string>
  {
    let stringToReturn:string;


    try
    {
    this.context.msGraphClientFactory.getClient('3')
    .then((client: MSGraphClientV3): void => {
      client.api('groups/<GUID>/members')
      .get((error: any, response: any, rawResponse?: any) => {

          const members: MicrosoftGraph.User[] = response.value;

          for (const memberDetail of members){
            console.log('memberDetail.mail:' + memberDetail.mail);
            stringToReturn = memberDetail.mail + "<br>";
          }

        });
    });

    }catch(e){
      
      stringToReturn = e.message.toString();

    }

Answer 1

您不會退回 Promise。

要么你 go 與異步等待風格

    var client = await this.context.msGraphClientFactory.getClient('3');
    var result = await client.api(...).get();
    //do something with the result here
    return stringToReturn;

或者你可以做類似的事情

return new Promise((resolve) => {
    this.context.msGraphClientFactory.getClient('3')
    .then((client: MSGraphClientV3): void => {
      client.api('groups/<GUID>/members')
      .get((error: any, response: any, rawResponse?: any) => {

          const members: MicrosoftGraph.User[] = response.value;

          for (const memberDetail of members){
            console.log('memberDetail.mail:' + memberDetail.mail);
            stringToReturn = memberDetail.mail + "<br>";
          }
          //when your string is ready return by resolving it
          resolve(stringToReturn);
        });
    });
 });