Feat：新增支持txt文件的导出

simple-mind-map/src/parse/toTxt.js

@@ -0,0 +1,35 @@
+import { walk, nodeRichTextToTextWithWrap } from '../utils'
+
+const getNodeText = data => {
+  return data.richText ? nodeRichTextToTextWithWrap(data.text) : data.text
+}
+
+const getIndent = level => {
+  return new Array(level).fill('   ').join('')
+}
+
+// 转换成txt格式
+export const transformToTxt = root => {
+  let content = ''
+  walk(
+    root,
+    null,
+    (node, parent, isRoot, layerIndex) => {
+      content += getIndent(layerIndex)
+      content += ' ' + getNodeText(node.data)
+      // 概要
+      const generalization = node.data.generalization
+      if (Array.isArray(generalization)) {
+        content += generalization.map(item => {
+          return ` [${getNodeText(item)}]`
+        })
+      } else if (generalization && generalization.text) {
+        content += ` [${getNodeText(generalization)}]`
+      }
+      content += '\n\n'
+    },
+    () => {},
+    true
+  )
+  return content
+}

simple-mind-map/src/plugins/Export.js

@@ -10,6 +10,7 @@ import { SVG } from '@svgdotjs/svg.js'
 import drawBackgroundImageToCanvas from '../utils/simulateCSSBackgroundInCanvas'
 import { transformToMarkdown } from '../parse/toMarkdown'
 import { ERROR_TYPES } from '../constants/constant'
+import { transformToTxt } from '../parse/toTxt'
 
 //  导出插件
 class Export {
@@ -294,6 +295,15 @@ class Export {
     const res = await readBlob(blob)
     return res
   }
+
+  // txt文件
+  async txt() {
+    const data = this.mindMap.getData()
+    const content = transformToTxt(data)
+    const blob = new Blob([content])
+    const res = await readBlob(blob)
+    return res
+  }
 }
 
 Export.instanceName = 'doExport'

simple-mind-map/src/utils/index.js

@@ -4,6 +4,7 @@ import {
   selfCloseTagList
 } from '../constants/constant'
 import MersenneTwister from './mersenneTwister'
+
 //  深度优先遍历树
 export const walk = (
   root,