extractText()

遞迴擷取 HAST 節點中的所有文字內容。

import { extractText } from "@unifast/core";

函式簽名

function extractText(node: HastNode): string

參數

node

屬性	型別	預設值	說明
`type`	`string`	—	節點型別（`"root"`、`"element"`、`"text"` 等）
`children`	`HastNode[]`	—	子節點（適用於 `"root"` 與 `"element"` 型別）
`value`	`string`	—	文字內容（適用於 `"text"` 型別）

回傳值

string — 從該節點及其所有子節點串接而成的全部文字內容。

用法

import { extractText } from "@unifast/core";
import type { HastElement } from "@unifast/core";

const element: HastElement = {
  type: "element",
  tagName: "p",
  properties: {},
  children: [
    { type: "text", value: "Hello " },
    {
      type: "element",
      tagName: "strong",
      properties: {},
      children: [{ type: "text", value: "world" }],
    },
  ],
};

const text = extractText(element);

console.log(text);
// Hello world

範例

從簡單元素擷取

import { extractText } from "@unifast/core";
import type { HastElement } from "@unifast/core";

const heading: HastElement = {
  type: "element",
  tagName: "h1",
  properties: { id: "title" },
  children: [{ type: "text", value: "Getting Started" }],
};

console.log(extractText(heading));
// Getting Started

從巢狀元素擷取

import { extractText } from "@unifast/core";
import type { HastElement } from "@unifast/core";

const paragraph: HastElement = {
  type: "element",
  tagName: "p",
  properties: {},
  children: [
    { type: "text", value: "This is " },
    {
      type: "element",
      tagName: "em",
      properties: {},
      children: [
        { type: "text", value: "deeply " },
        {
          type: "element",
          tagName: "strong",
          properties: {},
          children: [{ type: "text", value: "nested" }],
        },
      ],
    },
    { type: "text", value: " content." },
  ],
};

console.log(extractText(paragraph));
// This is deeply nested content.

空元素

import { extractText } from "@unifast/core";
import type { HastElement } from "@unifast/core";

const emptyDiv: HastElement = {
  type: "element",
  tagName: "div",
  properties: {},
  children: [],
};

console.log(extractText(emptyDiv));
// (empty string)

產生標題 slug

import { extractText } from "@unifast/core";
import type { HastElement } from "@unifast/core";

const heading: HastElement = {
  type: "element",
  tagName: "h2",
  properties: {},
  children: [
    { type: "text", value: "API " },
    {
      type: "element",
      tagName: "code",
      properties: {},
      children: [{ type: "text", value: "Reference" }],
    },
  ],
};

const slug = extractText(heading).toLowerCase().replace(/\s+/g, "-");

console.log(slug);
// api-reference