ConstrainBoolean

ConstrainBoolean dictionary is used to specify a constraint for a property whose value is a Boolean value. You can specify an exact value which must be matched, an ideal value that should be matched if at all possible, and a fallback value to attempt to match once all more specific constraints have been applied.

特性

exact
A Boolean which indicates a value the property must have.
ideal
A Boolean value indicating the ideal, but not required, value the property should ideally have. If possible, this value will be used, but the user agent will use the other value if it needs to in order to come up with a workable configuration.

You can also specify the value of the property as simply true or false , in which case the user agent will use that value if possible once all efforts have been made to match the exact and ideal values for other properties.

规范

规范 状态 Comment
媒体捕获和流
The definition of 'ConstrainBoolean' in that specification.
候选推荐 初始定义

Technically, ConstrainBoolean is actually based on an intermediary dictionary named ConstrainBooleanParameters , which adds exact and ideal to the simple Boolean type. However, for the sake of documentation clarity, the intermediate type (present only because of quirks in WebIDL syntax) is ignored here.

浏览器兼容性

更新 GitHub 上的兼容性数据
Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
ConstrainBoolean Chrome Yes Edge ≤79 Firefox 50 IE No Opera Yes Safari ? WebView Android Yes Chrome Android Yes Firefox Android 50 Opera Android Yes Safari iOS ? Samsung Internet Android Yes

图例

完整支持
完整支持
不支持
不支持
兼容性未知
兼容性未知

另请参阅