rails image_tag生成图片标签

image_tag(source, options={})Link

Returns an HTML image tag for thesource. Thesource can be a full path or a file.

Options

You can add HTML attributes using theoptions. Theoptions supports three additionalkeys for convenience and conformance:

• :alt - If no alt text is given, the file name part of thesource is used (capitalized and without the extension)

• :size - Supplied as "{Width}x{Height}" or "{Number}", so"30x45" becomes width="30" and height="45", and "50" becomes width="50" andheight="50".:size will be ignored if the value is not in thecorrect format.

Examples

image_tag("icon")# => <img alt="Icon" src="/assets/icon" />image_tag("icon.png")# => <img alt="Icon" src="/assets/icon.png" />image_tag("icon.png", size: "16x10", alt: "Edit Entry")# => <img src="/assets/icon.png" width="16" height="10" alt="Edit Entry" />image_tag("/icons/icon.gif", size: "16")# => <img src="/icons/icon.gif" width="16" height="16" alt="Icon" />image_tag("/icons/icon.gif", height: '32', width: '32')# => <img alt="Icon" height="32" src="/icons/icon.gif" width="32" />image_tag("/icons/icon.gif", class: "menu_icon")# => <img alt="Icon" class="menu_icon" src="/icons/icon.gif" />