HTML5 HTML5 Canvas and Graphics 1 — Questions and Answers
Question 1: Which method is used to get a 2D drawing context from an HTML5 canvas element?
- getContext('2d') (Correct answer)
- getContext('canvas')
- getDrawingContext()
- context2D()
Correct answer: getContext('2d')
The getContext('2d') method returns a CanvasRenderingContext2D object used for drawing shapes, text, and images on the canvas.
Question 2: What does the canvas fillRect() method do?
- Draws a filled rectangle at the specified position (Correct answer)
- Draws only the outline of a rectangle
- Clears a rectangular area
- Defines a clipping rectangle
Correct answer: Draws a filled rectangle at the specified position
The fillRect(x, y, width, height) method draws a filled solid rectangle using the current fillStyle.
Question 3: Which canvas method is used to draw an arc or circle?
- arc() (Correct answer)
- circle()
- drawCircle()
- ellipse()
Correct answer: arc()
The arc(x, y, radius, startAngle, endAngle, anticlockwise) method adds an arc to the current path, used to draw circles and circular shapes.
Question 4: What is the purpose of beginPath() in HTML5 Canvas?
- Starts a new drawing path, clearing any previous path (Correct answer)
- Begins a canvas fill operation
- Initializes the canvas context
- Opens a new canvas layer
Correct answer: Starts a new drawing path, clearing any previous path
The beginPath() method resets the current path so that subsequent path commands start fresh without connecting to old path segments.
Question 5: Which canvas property sets the color or style used to fill shapes?
- fillStyle (Correct answer)
- fillColor
- shapeColor
- paintStyle
Correct answer: fillStyle
The fillStyle property sets the color, gradient, or pattern used to fill shapes drawn on the canvas.
Question 6: What does the canvas clearRect() method do?
- Clears the specified rectangular area, making it transparent (Correct answer)
- Resets all canvas styles
- Removes the canvas element from the DOM
- Erases the last drawn shape only
Correct answer: Clears the specified rectangular area, making it transparent
The clearRect(x, y, width, height) method erases the pixels in the specified rectangle, making that area transparent.
Which method is used to get a 2D drawing context from an HTML5 canvas element?