From 33058f2b292b3a581333bdfb21b8f671898c5060 Mon Sep 17 00:00:00 2001 From: Peter Bengtsson Date: Tue, 8 Dec 2020 14:40:17 -0500 Subject: initial commit --- .../web/css/_colon_placeholder-shown/index.html | 92 ++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 files/zh-cn/web/css/_colon_placeholder-shown/index.html (limited to 'files/zh-cn/web/css/_colon_placeholder-shown') diff --git a/files/zh-cn/web/css/_colon_placeholder-shown/index.html b/files/zh-cn/web/css/_colon_placeholder-shown/index.html new file mode 100644 index 0000000000..86fd5a91c9 --- /dev/null +++ b/files/zh-cn/web/css/_colon_placeholder-shown/index.html @@ -0,0 +1,92 @@ +--- +title: ':placeholder-shown' +slug: 'Web/CSS/:placeholder-shown' +translation_of: 'Web/CSS/:placeholder-shown' +--- +
{{CSSRef}}{{SeeCompatTable}}
+ +

:placeholder-shown CSS 伪类 在 {{htmlElement("input")}} 或 {{htmlElement("textarea")}} 元素显示 placeholder text 时生效.

+ +
/* 选择所有显示占位符(placeholder)的元素 */
+:placeholder-shown {
+  border: 2px solid silver;
+}
+ +

参数

+ +
:placeholder-shown
+ +

样例

+ +

基础样例

+ +

HTML

+ +
<input placeholder="Type something here!">
+ +

CSS

+ +
input {
+  border: 2px solid black;
+  padding: 3px;
+}
+
+input:placeholder-shown {
+  border-color: silver;
+}
+ +

结果

+ +

{{EmbedLiveSample('Basic_example', 200, 60)}}

+ +

超出文本

+ +

在分辨率较小的设备上, 输入框或者其他表单控件可能会变的很窄. 这个选择器可以使得占位符文本缩短. 这个选择器经常和 {{cssxref("text-overflow")}} 一起使用.

+ +

HTML

+ +
<input placeholder="Enter something into this field, if you please!">
+ +

CSS

+ +
input:placeholder-shown {
+  text-overflow: ellipsis;
+}
+ +

结果

+ +

{{EmbedLiveSample("Overflowing_text", 200, 60)}}

+ +

规范

+ + + + + + + + + + + + + + + + +
SpecificationStatusComment
{{SpecName("CSS4 Selectors", "#placeholder", ":placeholder-shown")}}{{Spec2("CSS4 Selectors")}}Initial definition.
+ +

浏览器兼容性

+ + + +

{{Compat("css.selectors.placeholder-shown")}}

+ +

参见

+ + -- cgit v1.2.3-54-g00ecf