| JavaScript手册 | |
 |
目录 |
|
此参考中包含 的内容 |
|
轻松上手 |
|
简介 |
|
操作符 |
|
语句 |
|
核心 |
|
文档 |
|
窗口 |
|
表单 |
|
浏览器 |
|
事件和 事件句柄 |
|
LiveWire 数据库服务 |
|
进程管理服务 |
|
实用工具 |
|
全局函数 |
|
LiveConnect 的Java包 |
|
索引 |
|
|
onFocus
Executes JavaScript code when a focus event occurs; that is, when a window, frame, or frameset receives focus or when a form element receives input focus.
| 事件适用对象 | Button, Checkbox, FileUpload, Layer, Password, Radio, Reset, Select, Submit, Text, Textarea, Window |
| 实现版本 | Navigator 2.0 Navigator 3.0: event handler of Button, Checkbox, FileUpload, Frame, Password, Radio, Reset, Submit, and Window Navigator 4.0: event handler of Layer |
| handlerText | JavaScript 代码或对一个 JavaScript 函数的调用。 |
描述
The focus event can result from a focus method or from the user clicking the mouse on an object or window or tabbing with the keyboard. Selecting within a field results in a select event, not a focus event. onFocus executes JavaScript code when a focus event occurs.
A frame's onFocus event handler overrides an onFocus event handler in the BODY tag of the document loaded into frame.
Note that placing an alert in an onFocus event handler results in recurrent alerts: when you press OK to dismiss the alert, the underlying window gains focus again and produces another focus event.
Note
In Navigator 3.0, on some platforms, placing an onFocus event handler in a
FRAMESET tag has no effect.
使用的事件属性
| type | 标明了事件的类型。 |
| target | 标明了事件原来发送的对象。 |
示例
The following example uses an onFocus handler in the valueField Textarea object to call the valueCheck function.
<INPUT TYPE="textarea" VALUE="" NAME="valueField"
onFocus="valueCheck()">
See also示例 for onBlur.
【目录】 【上一页】 【下一页】 【索引】
回页面顶部