--- title: CanvasRenderingContext2D.textBaseline slug: Web/API/CanvasRenderingContext2D/textBaseline tags: - API - Canvas - Property translation_of: Web/API/CanvasRenderingContext2D/textBaseline ---
{{APIRef}}

CanvasRenderingContext2D.textBaseline - свойство Canvas 2D API, указывающее на текущую базовую линию при рисовании текста.

Синтаксис

ctx.textBaseline = "top" || "hanging" || "middle" || "alphabetic" || "ideographic" || "bottom";

Опции

Возможные значения:

"top"
The text baseline is the top of the em square.
"hanging"
The text baseline is the hanging baseline. (Used by Tibetan and other Indic scripts.)
"middle"
The text baseline is the middle of the em square.
"alphabetic"
The text baseline is the normal alphabetic baseline. Значение по умолчанию.
"ideographic"
The text baseline is the ideographic baseline; this is the bottom of the body of the characters, if the main body of characters protrudes beneath the alphabetic baseline. (Used by Chinese, Japanese, and Korean scripts.)
"bottom"
The text baseline is the bottom of the bounding box. This differs from the ideographic baseline in that the ideographic baseline doesn't consider descenders.

Примеры

Сравнение значений свойства

Этот пример демонстрирует различные значения свойства textBaseline и отображение линий при их приминениях.

HTML

<canvas id="canvas" width="550" height="500"></canvas>

JavaScript

const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');

const baselines = ['top', 'hanging', 'middle', 'alphabetic', 'ideographic', 'bottom'];
ctx.font = '36px serif';
ctx.strokeStyle = 'red';

baselines.forEach(function (baseline, index) {
  ctx.textBaseline = baseline;
  let y = 75 + index * 75;
  ctx.beginPath();
  ctx.moveTo(0, y + 0.5);
  ctx.lineTo(550, y + 0.5);
  ctx.stroke();
  ctx.fillText('Abcdefghijklmnop (' + baseline + ')', 0, y);
});

Результат

{{ EmbedLiveSample('Comparison_of_property_values', 700, 550) }}

Спецификации

Спецификация Статус Комментарий
{{SpecName('HTML WHATWG', "scripting.html#dom-context-2d-textbaseline", "CanvasRenderingContext2D.textBaseline")}} {{Spec2('HTML WHATWG')}}  

Поддержка браузерами

{{Compat("api.CanvasRenderingContext2D.textBaseline")}}

Смотрите также