Question

我有一个下拉列表工作正常，但是80个值列表的中间位置是我想要的默认值

$cosOptions = cos_options();

是变量

<td><select name="options"><?php print $cosOptions; ?></select></td>

打印下拉列表，然后打印下面的函数。

function cos_options()
{
    $dbh = dbh_get();
    $options = '';

    $sql = 'select code, descr FROM cos';
    $stmt = $dbh->prepare($sql);
    $stmt->execute();
    while (true) {
        $r = $stmt->fetch();
        if (is_bool($r)) break;
        $options .= '<option value="' . $r['code'] . ' ' . $r['descr'] . '">' . $r['code'] . ' ' . $r['descr'] . '</option>';
    }

    dbh_free($dbh);
    return $options;
}

Postgres表只有两列和80行

代码说明

D1 Pizza

D2面包

D3 Cornflakes等，

我需要的是首先选择 D43 Rice 因为90％的时间是这个。我怎样才能做到这一点？我在这里经历了很多帖子，但无法让它发挥作用。

Answer 1

您可以使用此代码选择D43Rice选项值。不要使用D43 Rice并合并D43Rice，有时文本空间会添加

<?php
while (true) {
    $r = $stmt->fetch();
    if (is_bool($r)) {
        break;
    }
    $selected = '';
    if ($r['code'].$r['descr'] == 'D43Rice') {
        $selected = 'selected="selected"';
    }
    $options .= '<option "' . $selected . '" value="' . $r['code'] . ' ' . $r['descr'] . '">' . $r['code'] . ' ' . $r['descr'] . '</option>';
}
?>

这是检查代码值的更新条件

<?php
while (true) {
    $r = $stmt->fetch();
    if (is_bool($r)) {
        break;
    }
    $selected = $r['code'].$r['descr'] = 'D43Rice' ? 'selected="selected"' : '';
    $options .= '<option "' . $selected . '" value="' . $r['code'] . ' ' . $r['descr'] . '">' . $r['code'] . ' ' . $r['descr'] . '</option>';
}
?>

Answer 2

function cos_options()
{
$dbh = dbh_get();
$options = '';

$sql = 'select code, descr FROM cos';
$stmt = $dbh->prepare($sql);
$stmt->execute();
while (true) {
    $r = $stmt->fetch();
    if (is_bool($r)) break;
    $temp=$r['code']. ' '. $r['descr'];
    if($temp=="D43 Rice") //check for whatever you want to set selected
    {
    $options .= '<option selected value="' . $r['code'] . ' ' . $r['descr'] . '">' . $r['code'] . ' ' . $r['descr'] . '</option>';
    }
    else
    {
    $options .= '<option value="' . $r['code'] . ' ' . $r['descr'] . '">' . $r['code'] . ' ' . $r['descr'] . '</option>';
    } 
}

dbh_free($dbh);
return $options;
}

Answer 3

<?php

if ($whateveryourneededcodeis == "D43") 
{
$selected = 'selected="selected"';
} else {
$selected = '';
}

$options .= '<option value="'.$r['code'].''.$r['descr'].'" $selected>'
.$r['code'].''.$r['descr'].'
</option>';

?>

PHP打印下拉列表，默认情况下从中间选择

3 个答案: