字幕列表 影片播放 列印英文字幕 The most useful and common input type is the text field. Like most form elements it requires the name attribute to be specified and the value attribute will be set to the text that it contains. Another useful input type is the password field, which hides its characters from view. For both of these types we can specify an initial value using the value attribute. We can also change the field's size, which is measured in number of character, or put a character limit on the field using the maxlength attribute. The last text field - hidden - is used to add data to a form without displaying it to the user. Because the user can't change this input type's value we must specify it in the markup. Next, we have checkboxes which are used to give multiple choices. If we don't specify a value a selected checkbox is sent with the value "TRUE". And if the box is unchecked no value will be sent for this element. With radio buttons only one button in every group can be checked. To group radio buttons together we just need to give them the same name. We can also make default selections using the checked attribute. <textarea> creates a multiline text box. The text between the tags is the default content and the size of the area is given with the cols and rows attributes. The last form control we can create are list boxes using the elements <select>, <option>, and option group <optgroup>. The <select> tag is the container for the list and gives the list its name. Inside of it we define each list item using the <option> element. If no value attribute is assigned, the content of the <option> element will be sent as the value if that option is selected. By default only one option is displayed, making the list box appear as a dropdown list. We can increase the number of displayed items using the size attribute, making the list box into a scroll list instead. To be able to select multiple options, we can enable the multiple attribute. And to select default options we can use the selected attribute. The option group tag is used to give a title for a set of options in order to group them together. The <fieldset> element creates a border around any form controls in order to group them visually. We may also provide a label for the fieldset using the <legend> tag.
B1 中級 HTML教程-14-表格二 (HTML Tutorial - 14 - Forms II) 104 6 Pan-Shy Gang 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字