TextMetrics.fontBoundingBoxAscent - Web APIs 编辑

The read-only fontBoundingBoxAscent property of the TextMetrics interface is a double giving the distance from the horizontal line indicated by the CanvasRenderingContext2D.textBaseline attribute to the top of the highest bounding rectangle of all the fonts used to render the text, in CSS pixels.

Examples

const canvas = document.createElement('canvas');
const ctx = canvas.getContext('2d');
const text = ctx.measureText('foo'); // returns TextMetrics object

text.fontBoundingBoxAscent; // 10;

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• TextMetrics