Question

我编写了一个从表中调用数组的函数

function fetchoperator($operator_type)
{
    global $mysqli; 
    $stmt = $mysqli->prepare("SELECT 
        id,
        operator_name   
    FROM gb_operators WHERE operator_type = ?
    ");
    $stmt->bind_param("s", $operator_type);
    $stmt->execute();
    $stmt->bind_result($id,$operator_name);
    while ($stmt->fetch()){
        $row = array('id' => $id, 'operator_name' => $operator_name);
    }
    $stmt->close();
    if(!empty($row))
    {
        return ($row);
    }
    else
    {
        return "";
    }
}

现在在主页

$oprtor=fetchoperator(1);

现在进入html页面

<select id="MPOperator" name="opr" class="form-control" required>
        <?php foreach($oprtor as $v2) {
            echo "<option value=".$v2['id'].">".$v2['operator_name']."</option>"; } ?>                                       
            </select>

现在当我在没有foreach（）函数的情况下使用时，我得到了表的最后一行的值，但是当我使用foreach函数时，我得到一个输出为V

但它应该显示14列。请帮我解决错误!!!!

Answer 1

您正在覆盖$row变量。这就是为什么你只获得最后一行。将其转换为$row[]，将行推入$row数组。

这样做

while ($stmt->fetch()){
    $row[] = array('id' => $id, 'operator_name' => $operator_name);
}

Answer 2

你没有填充一个数组，你已经多次写一个标量变量了

function fetchoperator($operator_type)
{
    global $mysqli; 
    $stmt = $mysqli->prepare("SELECT id, operator_name   
                              FROM gb_operators 
                              WHERE operator_type = ?
    ");
    $stmt->bind_param("s", $operator_type);
    $stmt->execute();
    $stmt->bind_result($id,$operator_name);
    while ($stmt->fetch()){
        // error here
        //$row = array('id' => $id, 'operator_name' => $operator_name);

        $row[] = array('id' => $id, 'operator_name' => $operator_name);
    }
    $stmt->close();
    if(!empty($row)) {
        return $row;
    } else {
        return "";
    }
}

Answer 3

使用array_push（）在数组中添加新值。在你的情况下。你只需要为数组设置一个新值。

constructor (){
    super();
    this.state = {
        sortType: 'top' //default is to sort by Top
    };

    this.setSortType = this.setSortType.bind(this);
}
componentWillMount(){
    //this retrieves sourceName which is required to make the API call
    const parsed = queryString.parse(this.props.location.search);
    var sourceName = parsed.sourceId;

    //getArticles below is the action that makes the API call with sourcename and sortType as parameters  

    newsActions.getArticles(sourceName,this.state.sortType);
    newsStore.on('articles_change',this.fetchNewsArticles);

}
//Call to setState when user clicks button change sort parameter
setSortType(){
    this.setState({
        sortType:'latest'
    });
}

render() {
    return (
        <div>
        ... //logic to display data from the API call 
        <button onClick={this.setSortType}> Sort By Latest </button>
        </div>
    );
}

foreach（）函数导致错误

3 个答案: