PHP-预选下拉选项 [英] PHP - PRE-select drop down option

问题描述

在以下URL使用示例: http://www.kavoir.com/2009/02/php-drop-down-list.html

Using the example at the following URL: http://www.kavoir.com/2009/02/php-drop-down-list.html

我如何使该下拉菜单预先选择诸如"Apple"之类的选项之一?

How can I have that drop down menu pre-select one of the options such as 'Apple'?

添加信息

function showForm()

{
global $sProduct, $name, $product, $header_file, $footer_file, $form_width, $form_background, $form_border_color, $form_border_width, $form_border_style, $cell_padding, $left_col_width, $font_size;   
include $header_file; 
echo <<<EOD

<form method="post" class="cForm">
<table style="width:{$form_width}; padding:20px 7px 0px 7px; font-size:{$font_size}; background-color:{$form_background};" class="contactForm">
<tr>
<td style="width:{$left_col_width}; text-align:left; vertical-align:center; padding:{$cell_padding}; font-weight:bold; {$name[3]}">{$name[0]}</td>
<td style="text-align:left; vertical-align:top; padding:{$cell_padding};"><input type="text" name="{$name[1]}" value="{$name[2]}" size="25"/></td>
</tr>
<tr>
<td style="width:{$left_col_width}; text-align:left; vertical-align:center; padding:{$cell_padding}; font-weight:bold;">{$product[0]}</td>
<!--<td style="text-align:left; vertical-align:top; padding:{$cell_padding};"><select name="{$product[1]}">-->
<td style="text-align:left; vertical-align:top; padding:{$cell_padding};">
<select name="{$product[1]}">
    <option value="1"></option>
    <option value="2">item 2</option>
    <option value="3">item 3</option>
    <option value="4">item 4</option>
    <option value="5">item 5</option>
    <option value="6">item 6</option>
</select>
</td>
</tr>
<td style="width:{$left_col_width}; text-align:left; vertical-align:center; padding:{$cell_padding}; font-weight:bold; {$code[3]}">{$code[0]}</td>
<td style="text-align:left; vertical-align:top; padding:{$cell_padding};"><input type="submit" name="submit" value="Submit" style="border:1px solid #999;background:#E4E4E4;" /></td>
</tr>
<tr>
<td colspan="2" style="font-size:10px; text-align:left; vertical-align:middle; padding:{$cell_padding};">
0:(var_product[0] = ({$product[0]})) <br/>
1:(var_product[1] = ({$product[1]})) <br/>
2:(var_product[2] = ({$product[2]}))<br/>
3:(var_product[3] = ({$product[3]}))<br/>
4:(var_sProduct = ({$sProduct}))<br/>
</td>
</tr>
</table>
</form>

EOD;

推荐答案

我将向generateSelect函数添加另一个参数，该参数定义默认值.您可以使用选项的id或name来执行此操作.对于以下内容，我将使用name使其更清晰.

I would throw another parameter into the generateSelect function that defines what the default is. You can do this with either the id of the option or by the name. For the following, I'll use name to make it clearer.

function generateSelect($name = '', $options = array(), $default = '') {
    $html = '<select name="'.$name.'">';
    foreach ($options as $option => $value) {
        if ($option == $default) {
            $html .= '<option value='.$value.' selected="selected">'.$option.'</option>';
        } else {
            $html .= '<option value='.$value.'>'.$option.'</option>';
        }
    }

    $html .= '</select>';
    return $html;
}

/* And then call it like */
$html = generateSelect('company', $companies, 'Apple');

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