img、input标签它们是行内元素还是块级元素？

img and input are both inline elements, but they behave a bit like inline-block elements. Let's break down why:

• Historically Inline: By default, both img and input elements are inline. This means they flow within the text content of a line and don't force line breaks before or after themselves.

• Replaced Elements & Inline-Block Behavior: Both img and input are considered "replaced elements." This means their content is rendered externally and the browser determines their dimensions based on the replaced content (the image for img, and the browser's default styling for input). Because of this, they behave similarly to inline-block elements in terms of:

  • Width and Height: You can set explicit width and height properties on them, and they will respect those dimensions.
  • Padding and Margin: padding and margin apply to all four sides (top, right, bottom, left), unlike regular inline elements where only horizontal margins and padding have an effect.
  • Vertical Alignment: They can be vertically aligned using properties like vertical-align.

• In Summary: While technically categorized as inline, their replaced nature gives them layout characteristics very similar to inline-block elements. Think of them as inline elements that you can size and position more like block-level elements.

Therefore, the most accurate answer is that they are inline elements that behave like inline-block elements due to being replaced elements.