From 33058f2b292b3a581333bdfb21b8f671898c5060 Mon Sep 17 00:00:00 2001 From: Peter Bengtsson Date: Tue, 8 Dec 2020 14:40:17 -0500 Subject: initial commit --- .../canvasrenderingcontext2d/filltext/index.html | 170 +++++++++++++++++++++ 1 file changed, 170 insertions(+) create mode 100644 files/zh-cn/web/api/canvasrenderingcontext2d/filltext/index.html (limited to 'files/zh-cn/web/api/canvasrenderingcontext2d/filltext') diff --git a/files/zh-cn/web/api/canvasrenderingcontext2d/filltext/index.html b/files/zh-cn/web/api/canvasrenderingcontext2d/filltext/index.html new file mode 100644 index 0000000000..6cbff0639b --- /dev/null +++ b/files/zh-cn/web/api/canvasrenderingcontext2d/filltext/index.html @@ -0,0 +1,170 @@ +--- +title: CanvasRenderingContext2D.fillText() +slug: Web/API/CanvasRenderingContext2D/fillText +translation_of: Web/API/CanvasRenderingContext2D/fillText +--- +
{{APIRef}}
+ +

CanvasRenderingContext2D.fillText() 是 Canvas 2D API 在 (x, y)位置填充文本的方法。如果选项的第四个参数提供了最大宽度，文本会进行缩放以适应最大宽度。

+ +

参见 {{domxref("CanvasRenderingContext2D.strokeText()")}} 方法对文本进行描边。

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语法

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void ctx.fillText(text, x, y, [maxWidth]);
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+ +

参数

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+
text
+
使用当前的 {{domxref("CanvasRenderingContext2D.font","font")}}, {{domxref("CanvasRenderingContext2D.textAlign","textAlign")}}, {{domxref("CanvasRenderingContext2D.textBaseline","textBaseline")}} 和 {{domxref("CanvasRenderingContext2D.direction","direction")}} 值对文本进行渲染。
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+ +
+
x
+
文本起点的 x 轴坐标。
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y
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文本起点的 y 轴坐标。
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maxWidth {{optional_inline}}
+
绘制的最大宽度。如果指定了值，并且经过计算字符串的值比最大宽度还要宽，字体为了适应会水平缩放（如果通过水平缩放当前字体，可以进行有效的或者合理可读的处理）或者使用小号的字体。
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+ +

示例

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使用 fillText 方法

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这是一段使用 fillText 方法的简单的代码片段。

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HTML

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<canvas id="canvas"></canvas>
+
+ +

JavaScript

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var canvas = document.getElementById("canvas");
+var ctx = canvas.getContext("2d");
+
+ctx.font = "48px serif";
+ctx.fillText("Hello world", 50, 100);
+
+ +

修改下面的代码并在线查看 canvas 的变化：

+ +
+
Playable code
+ +
<canvas id="canvas" width="400" height="200" class="playable-canvas"></canvas>
+<div class="playable-buttons">
+  <input id="edit" type="button" value="Edit" />
+  <input id="reset" type="button" value="Reset" />
+</div>
+<textarea id="code" class="playable-code">
+ctx.font = "48px serif";
+ctx.fillText("Hello world", 50, 100);</textarea>
+
+ +
var canvas = document.getElementById("canvas");
+var ctx = canvas.getContext("2d");
+var textarea = document.getElementById("code");
+var reset = document.getElementById("reset");
+var edit = document.getElementById("edit");
+var code = textarea.value;
+
+function drawCanvas() {
+  ctx.clearRect(0, 0, canvas.width, canvas.height);
+  eval(textarea.value);
+}
+
+reset.addEventListener("click", function() {
+  textarea.value = code;
+  drawCanvas();
+});
+
+edit.addEventListener("click", function() {
+  textarea.focus();
+})
+
+textarea.addEventListener("input", drawCanvas);
+window.addEventListener("load", drawCanvas);
+
+
+ +

{{ EmbedLiveSample('Playable_code', 700, 360) }}

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规范描述

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SpecificationStatusComment
{{SpecName('HTML WHATWG', "scripting.html#dom-context-2d-filltext", "CanvasRenderingContext2D.fillText")}}{{Spec2('HTML WHATWG')}}
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浏览器兼容性

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{{ CompatibilityTable() }}

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FeatureChromeFirefox (Gecko)Internet ExplorerOperaSafari
Basic support{{ CompatVersionUnknown() }}{{ CompatGeckoDesktop("1.9.1") }}{{ CompatIE(9) }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}
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+ + + + + + + + + + + + + + + + + + + + + +
FeatureAndroidChrome for AndroidFirefox Mobile (Gecko)IE MobileOpera MobileSafari Mobile
Basic support{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatGeckoMobile("1.9.1") }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}
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参见

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