表單輔助函數

表單輔助涵式檔案包含與型式互動的輔助功能

載入此輔助函數

此輔助函數可以利用以下的程式碼讀取:

helper('form');

脫離領欄位的值

你或許需要使用 HTML 與像是引用的字元在你的型式元素中。 為了安全的實作,你會需要使用 common function esc().

以底下的範例為考量:

$string = 'Here is a string containing "quoted" text.';

<input type="text" name="myfield" value="<?= $string; ?>" />

由於上述的字串包含一組引用,他將會造成型式破裂 esc() 功能會轉換特殊的 HTML 字元以便它可以安全地被利用:

<input type="text" name="myfield" value="<?= esc($string); ?>" />

備註

如果你使用此頁面所列出的任一 form 輔助函數,並且你傳遞值作為關聯陣列, form 的值會被自動脫離,因此你沒有必要呼叫此函式。只有你在建立你自己的 form 元素的時候使用,在你會以字串型式傳遞的時候使用

可用的功能

以下敘述的功能皆可用:

form_open([$action = ''[, $attributes = ''[, $hidden = []]]])
參數:
  • $action (string) – Form 動作/目標 URI 字串
  • $attributes (mixed) – HTML 屬性,是一個陣列或跳脫的字串
  • $hidden (array) – 一個隱藏欄位的定義陣列
傳回:

HTML form 開啟標籤

傳回型態:

string

建立一個啟動標籤內含一個 從你的配置偏好建立的 基礎 URL。
它將會讓你選擇增加 form 屬性與隱藏輸入區,同時也會根據你的 config 檔案中的 charset 值永遠增加 accept-charset 屬性。

使用這個標籤而不是強硬的編寫你自己的 HTML 程式的主要好處是它將會讓你的網站在變更 URL 時更輕便

這是一個簡單的範例:

echo form_open('email/send');

上述的範例會建立一個 form 指向你的基礎 URL 加上 「email/send」 URI 段落,像是這個:

<form method="post" accept-charset="utf-8" action="http://example.com/index.php/email/send">

增加屬性

屬性可以透過傳遞一個關聯的陣列到第二個參數來增加,像是這樣:

$attributes = ['class' => 'email', 'id' => 'myform'];
echo form_open('email/send', $attributes);

或者,你可以指定第二個參數為一個字串:

echo form_open('email/send', 'class="email" id="myform"');

上述的範例會產生一個類似於這個的 form:

<form method="post" accept-charset="utf-8" action="http://example.com/index.php/email/send" class="email" id="myform">

如果 CSRF 過濾器是開啟的,form_open() 將會在 form 的最一開始產生 CSRF 欄位。你可以透過將 csrf_id 作為其中一個 $attribute 陣列傳送進 form 以指定這個欄位的ID:

form_open(『/u/sign-up』, [『csrf_id』 => 『my-id』]);

它將會回傳:

<form action=」/u/sign-up」 method=」post」 accept-charset=」utf-8」> <input type=」hidden」 id=」my-id」 name=」csrf_field」 value=」964ede6e0ae8a680f7b8eab69136717d」 />

增加隱藏的輸入欄位

隱藏的輸入欄位可以藉由傳送一個關聯的陣列到第三個參數以增加,項是這樣:

$hidden = ['username' => 'Joe', 'member_id' => '234'];
echo form_open('email/send', '', $hidden);

你可以透過傳遞任何 false 值到第二參數以跳過第二個參數。

上述的範例會產生一個類似於這個的 form:

<form method="post" accept-charset="utf-8" action="http://example.com/index.php/email/send">
        <input type="hidden" name="username" value="Joe" />
        <input type="hidden" name="member_id" value="234" />
form_open_multipart([$action = ''[, $attributes = ''[, $hidden = []]]])
參數:
  • $action (string) – Form 動作/目標 URI 字串
  • $attributes (mixed) – HTML 屬性,是一個陣列或跳脫的字串
  • $hidden (array) – 一個隱藏欄位的定義陣列
傳回:

HTML multipart 多部份的 form 開啟標籤

傳回型態:

string

This function is identical to form_open() above, except that it adds a multipart attribute, which is necessary if you would like to use the form to upload files with.

form_hidden($name[, $value = ''])
參數:
  • $name (string) – Field name
  • $value (string) – Field value
傳回:

An HTML hidden input field tag

傳回型態:

string

Lets you generate hidden input fields. You can either submit a name/value string to create one field:

form_hidden('username', 'johndoe');
// Would produce: <input type="hidden" name="username" value="johndoe" />

… or you can submit an associative array to create multiple fields:

$data = [
        'name'  => 'John Doe',
        'email' => 'john@example.com',
        'url'   => 'http://example.com'
];

echo form_hidden($data);

/*
        Would produce:
        <input type="hidden" name="name" value="John Doe" />
        <input type="hidden" name="email" value="john@example.com" />
        <input type="hidden" name="url" value="http://example.com" />
*/

You can also pass an associative array to the value field:

$data = [
        'name'  => 'John Doe',
        'email' => 'john@example.com',
        'url'   => 'http://example.com'
];

echo form_hidden('my_array', $data);

/*
        Would produce:

        <input type="hidden" name="my_array[name]" value="John Doe" />
        <input type="hidden" name="my_array[email]" value="john@example.com" />
        <input type="hidden" name="my_array[url]" value="http://example.com" />
*/

If you want to create hidden input fields with extra attributes:

$data = [
        'type'  => 'hidden',
        'name'  => 'email',
        'id'    => 'hiddenemail',
        'value' => 'john@example.com',
        'class' => 'hiddenemail'
];

echo form_input($data);

/*
        Would produce:

        <input type="hidden" name="email" value="john@example.com" id="hiddenemail" class="hiddenemail" />
*/
form_input([$data = ''[, $value = ''[, $extra = ''[, $type = 'text']]]])
參數:
  • $data (array) – Field attributes data
  • $value (string) – Field value
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
  • $type (string) – The type of input field. i.e. 『text』, 『email』, 『number』, etc.
傳回:

An HTML text input field tag

傳回型態:

string

Lets you generate a standard text input field. You can minimally pass the field name and value in the first and second parameter:

echo form_input('username', 'johndoe');

Or you can pass an associative array containing any data you wish your form to contain:

$data = [
        'name'      => 'username',
        'id'        => 'username',
        'value'     => 'johndoe',
        'maxlength' => '100',
        'size'      => '50',
        'style'     => 'width:50%'
];

echo form_input($data);

/*
        Would produce:

        <input type="text" name="username" value="johndoe" id="username" maxlength="100" size="50" style="width:50%"  />
*/

If you would like your form to contain some additional data, like JavaScript, you can pass it as a string in the third parameter:

$js = 'onClick="some_function()"';
echo form_input('username', 'johndoe', $js);

Or you can pass it as an array:

$js = ['onClick' => 'some_function();'];
echo form_input('username', 'johndoe', $js);

To support the expanded range of HTML5 input fields, you can pass an input type in as the fourth parameter:

echo form_input('email', 'joe@example.com', ['placeholder' => 'Email Address...'], 'email');

/*
         Would produce:

        <input type="email" name="email" value="joe@example.com" placeholder="Email Address..." />
*/
form_password([$data = ''[, $value = ''[, $extra = '']]])
參數:
  • $data (array) – Field attributes data
  • $value (string) – Field value
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML password input field tag

傳回型態:

string

This function is identical in all respects to the form_input() function above except that it uses the 「password」 input type.

form_upload([$data = ''[, $value = ''[, $extra = '']]])
參數:
  • $data (array) – Field attributes data
  • $value (string) – Field value
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML file upload input field tag

傳回型態:

string

This function is identical in all respects to the form_input() function above except that it uses the 「file」 input type, allowing it to be used to upload files.

form_textarea([$data = ''[, $value = ''[, $extra = '']]])
參數:
  • $data (array) – Field attributes data
  • $value (string) – Field value
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML textarea tag

傳回型態:

string

This function is identical in all respects to the form_input() function above except that it generates a 「textarea」 type.

備註

Instead of the maxlength and size attributes in the above example, you will instead specify rows and cols.

form_dropdown([$name = ''[, $options = [][, $selected = [][, $extra = '']]]])
參數:
  • $name (string) – Field name
  • $options (array) – An associative array of options to be listed
  • $selected (array) – List of fields to mark with the selected attribute
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML dropdown select field tag

傳回型態:

string

Lets you create a standard drop-down field. The first parameter will contain the name of the field, the second parameter will contain an associative array of options, and the third parameter will contain the value you wish to be selected. You can also pass an array of multiple items through the third parameter, and the helper will create a multiple select for you.

Example:

$options = [
        'small'  => 'Small Shirt',
        'med'    => 'Medium Shirt',
        'large'  => 'Large Shirt',
        'xlarge' => 'Extra Large Shirt',
];

$shirts_on_sale = ['small', 'large'];
echo form_dropdown('shirts', $options, 'large');

/*
        Would produce:

        <select name="shirts">
                <option value="small">Small Shirt</option>
                <option value="med">Medium Shirt</option>
                <option value="large" selected="selected">Large Shirt</option>
                <option value="xlarge">Extra Large Shirt</option>
        </select>
*/

echo form_dropdown('shirts', $options, $shirts_on_sale);

/*
        Would produce:

        <select name="shirts" multiple="multiple">
                <option value="small" selected="selected">Small Shirt</option>
                <option value="med">Medium Shirt</option>
                <option value="large" selected="selected">Large Shirt</option>
                <option value="xlarge">Extra Large Shirt</option>
        </select>
*/

If you would like the opening <select> to contain additional data, like an id attribute or JavaScript, you can pass it as a string in the fourth parameter:

$js = 'id="shirts" onChange="some_function();"';
echo form_dropdown('shirts', $options, 'large', $js);

Or you can pass it as an array:

$js = [
        'id'       => 'shirts',
        'onChange' => 'some_function();'
];
echo form_dropdown('shirts', $options, 'large', $js);

If the array passed as $options is a multidimensional array, then form_dropdown() will produce an <optgroup> with the array key as the label.

form_multiselect([$name = ''[, $options = [][, $selected = [][, $extra = '']]]])
參數:
  • $name (string) – Field name
  • $options (array) – An associative array of options to be listed
  • $selected (array) – List of fields to mark with the selected attribute
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML dropdown multiselect field tag

傳回型態:

string

Lets you create a standard multiselect field. The first parameter will contain the name of the field, the second parameter will contain an associative array of options, and the third parameter will contain the value or values you wish to be selected.

The parameter usage is identical to using form_dropdown() above, except of course that the name of the field will need to use POST array syntax, e.g. foo[].

form_fieldset([$legend_text = ''[, $attributes = []]])
參數:
  • $legend_text (string) – Text to put in the <legend> tag
  • $attributes (array) – Attributes to be set on the <fieldset> tag
傳回:

An HTML fieldset opening tag

傳回型態:

string

Lets you generate fieldset/legend fields.

Example:

echo form_fieldset('Address Information');
echo "<p>fieldset content here</p>\n";
echo form_fieldset_close();

/*
        Produces:

                <fieldset>
                        <legend>Address Information</legend>
                                <p>form content here</p>
                </fieldset>
*/

Similar to other functions, you can submit an associative array in the second parameter if you prefer to set additional attributes:

$attributes = [
        'id'    => 'address_info',
        'class' => 'address_info'
];

echo form_fieldset('Address Information', $attributes);
echo "<p>fieldset content here</p>\n";
echo form_fieldset_close();

/*
        Produces:

        <fieldset id="address_info" class="address_info">
                <legend>Address Information</legend>
                <p>form content here</p>
        </fieldset>
*/
form_fieldset_close([$extra = ''])
參數:
  • $extra (string) – Anything to append after the closing tag, as is
傳回:

An HTML fieldset closing tag

傳回型態:

string

Produces a closing </fieldset> tag. The only advantage to using this function is it permits you to pass data to it which will be added below the tag. For example

$string = '</div></div>';
echo form_fieldset_close($string);
// Would produce: </fieldset></div></div>
form_checkbox([$data = ''[, $value = ''[, $checked = FALSE[, $extra = '']]]])
參數:
  • $data (array) – Field attributes data
  • $value (string) – Field value
  • $checked (bool) – Whether to mark the checkbox as being checked
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML checkbox input tag

傳回型態:

string

Lets you generate a checkbox field. Simple example:

echo form_checkbox('newsletter', 'accept', TRUE);
// Would produce:  <input type="checkbox" name="newsletter" value="accept" checked="checked" />

The third parameter contains a boolean TRUE/FALSE to determine whether the box should be checked or not.

Similar to the other form functions in this helper, you can also pass an array of attributes to the function:

$data = [
        'name'    => 'newsletter',
        'id'      => 'newsletter',
        'value'   => 'accept',
        'checked' => TRUE,
        'style'   => 'margin:10px'
];

echo form_checkbox($data);
// Would produce: <input type="checkbox" name="newsletter" id="newsletter" value="accept" checked="checked" style="margin:10px" />

Also as with other functions, if you would like the tag to contain additional data like JavaScript, you can pass it as a string in the fourth parameter:

$js = 'onClick="some_function()"';
echo form_checkbox('newsletter', 'accept', TRUE, $js);

Or you can pass it as an array:

$js = ['onClick' => 'some_function();'];
echo form_checkbox('newsletter', 'accept', TRUE, $js);
form_radio([$data = ''[, $value = ''[, $checked = FALSE[, $extra = '']]]])
參數:
  • $data (array) – Field attributes data
  • $value (string) – Field value
  • $checked (bool) – Whether to mark the radio button as being checked
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML radio input tag

傳回型態:

string

This function is identical in all respects to the form_checkbox() function above except that it uses the 「radio」 input type.

form_label([$label_text = ''[, $id = ''[, $attributes = []]]])
參數:
  • $label_text (string) – Text to put in the <label> tag
  • $id (string) – ID of the form element that we’re making a label for
  • $attributes (string) – HTML attributes
傳回:

An HTML field label tag

傳回型態:

string

Lets you generate a <label>. Simple example:

echo form_label('What is your Name', 'username');
// Would produce:  <label for="username">What is your Name</label>

Similar to other functions, you can submit an associative array in the third parameter if you prefer to set additional attributes.

Example:

$attributes = [
        'class' => 'mycustomclass',
        'style' => 'color: #000;'
];

echo form_label('What is your Name', 'username', $attributes);
// Would produce:  <label for="username" class="mycustomclass" style="color: #000;">What is your Name</label>
form_submit([$data = ''[, $value = ''[, $extra = '']]])
參數:
  • $data (string) – Button name
  • $value (string) – Button value
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML input submit tag

傳回型態:

string

Lets you generate a standard submit button. Simple example:

echo form_submit('mysubmit', 'Submit Post!');
// Would produce:  <input type="submit" name="mysubmit" value="Submit Post!" />

Similar to other functions, you can submit an associative array in the first parameter if you prefer to set your own attributes. The third parameter lets you add extra data to your form, like JavaScript.

form_reset([$data = ''[, $value = ''[, $extra = '']]])
參數:
  • $data (string) – Button name
  • $value (string) – Button value
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML input reset button tag

傳回型態:

string

Lets you generate a standard reset button. Use is identical to form_submit().

form_button([$data = ''[, $content = ''[, $extra = '']]])
參數:
  • $data (string) – Button name
  • $content (string) – Button label
  • $extra (mixed) – Extra attributes to be added to the tag either as an array or a literal string
傳回:

An HTML button tag

傳回型態:

string

Lets you generate a standard button element. You can minimally pass the button name and content in the first and second parameter:

echo form_button('name','content');
// Would produce: <button name="name" type="button">Content</button>

Or you can pass an associative array containing any data you wish your form to contain:

$data = [
        'name'    => 'button',
        'id'      => 'button',
        'value'   => 'true',
        'type'    => 'reset',
        'content' => 'Reset'
];

echo form_button($data);
// Would produce: <button name="button" id="button" value="true" type="reset">Reset</button>

If you would like your form to contain some additional data, like JavaScript, you can pass it as a string in the third parameter:

$js = 'onClick="some_function()"';
echo form_button('mybutton', 'Click Me', $js);
form_close([$extra = ''])
參數:
  • $extra (string) – Anything to append after the closing tag, as is
傳回:

An HTML form closing tag

傳回型態:

string

Produces a closing </form> tag. The only advantage to using this function is it permits you to pass data to it which will be added below the tag. For example:

$string = '</div></div>';
echo form_close($string);
// Would produce:  </form> </div></div>
set_value($field[, $default = ''[, $html_escape = TRUE]])
參數:
  • $field (string) – Field name
  • $default (string) – Default value
  • $html_escape (bool) – Whether to turn off HTML escaping of the value
傳回:

Field value

傳回型態:

string

Permits you to set the value of an input form or textarea. You must supply the field name via the first parameter of the function. The second (optional) parameter allows you to set a default value for the form. The third (optional) parameter allows you to turn off HTML escaping of the value, in case you need to use this function in combination with i.e. form_input() and avoid double-escaping.

Example:

<input type="text" name="quantity" value="<?php echo set_value('quantity', '0'); ?>" size="50" />

The above form will show 「0」 when loaded for the first time.

set_select($field[, $value = ''[, $default = FALSE]])
參數:
  • $field (string) – Field name
  • $value (string) – Value to check for
  • $default (string) – Whether the value is also a default one
傳回:

『selected』 attribute or an empty string

傳回型態:

string

If you use a <select> menu, this function permits you to display the menu item that was selected.

The first parameter must contain the name of the select menu, the second parameter must contain the value of each item, and the third (optional) parameter lets you set an item as the default (use boolean TRUE/FALSE).

Example:

<select name="myselect">
        <option value="one" <?php echo  set_select('myselect', 'one', TRUE); ?> >One</option>
        <option value="two" <?php echo  set_select('myselect', 'two'); ?> >Two</option>
        <option value="three" <?php echo  set_select('myselect', 'three'); ?> >Three</option>
</select>
set_checkbox($field[, $value = ''[, $default = FALSE]])
參數:
  • $field (string) – Field name
  • $value (string) – Value to check for
  • $default (string) – Whether the value is also a default one
傳回:

『checked』 attribute or an empty string

傳回型態:

string

Permits you to display a checkbox in the state it was submitted.

The first parameter must contain the name of the checkbox, the second parameter must contain its value, and the third (optional) parameter lets you set an item as the default (use boolean TRUE/FALSE).

Example:

<input type="checkbox" name="mycheck" value="1" <?php echo set_checkbox('mycheck', '1'); ?> />
<input type="checkbox" name="mycheck" value="2" <?php echo set_checkbox('mycheck', '2'); ?> />
set_radio($field[, $value = ''[, $default = FALSE]])
參數:
  • $field (string) – Field name
  • $value (string) – Value to check for
  • $default (string) – Whether the value is also a default one
傳回:

『checked』 attribute or an empty string

傳回型態:

string

Permits you to display radio buttons in the state they were submitted. This function is identical to the set_checkbox() function above.

Example:

<input type="radio" name="myradio" value="1" <?php echo  set_radio('myradio', '1', TRUE); ?> />
<input type="radio" name="myradio" value="2" <?php echo  set_radio('myradio', '2'); ?> />

備註

If you are using the Form Validation class, you must always specify a rule for your field, even if empty, in order for the set_*() functions to work. This is because if a Form Validation object is defined, the control for set_*() is handed over to a method of the class instead of the generic helper function.