$sql= ("SELECT COUNT (id) AS total FROM grade ");
$result=mysqli_query($dbConnection, $sql);
echo $result['total'];
屏幕上没有任何内容。黑屏。表中有记录。
答案 0 :(得分：1)
您在 <ion-item *ngFor="let survey of surveys" (click)="openSurvey(survey)">
<ion-thumbnail item-start>
<img *ngIf="survey.icon" width="35" src="{{survey.icon}}"/>
<ion-icon *ngIf="!survey.icon" name="clipboard"></ion-icon>
</ion-thumbnail>
{{survey.label}}
<button (click)="showSurveyInfo($event, survey);$event.stopPropagation();" ion-button icon-only clear >
<ion-icon name="ios-information-circle-outline"></ion-icon>
</button>
<button ion-button item-end icon-only clear>
<ion-icon name="ios-arrow-forward"></ion-icon>
</button>
</ion-item>
和count之间留有一个空格，这将导致查询失败。
如果显示它们，确切的错误将是
(id)