ant-design-vue/components/vc-tree/demo/util.js

/* eslint no-loop-func: 0*/
/* eslint no-console:0 */

export function generateData (x = 3, y = 2, z = 1, gData = []) {
  // x：每一级下的节点总数。y：每级节点里有y个节点、存在子节点。z：树的level层级数（0表示一级）
  function _loop (_level, _preKey, _tns) {
    const preKey = _preKey || '0'
    const tns = _tns || gData

    const children = []
    for (let i = 0; i < x; i++) {
      const key = `${preKey}-${i}`
      tns.push({ title: `${key}-label`, key: `${key}-key` })
      if (i < y) {
        children.push(key)
      }
    }
    if (_level < 0) {
      return tns
    }
    const __level = _level - 1
    children.forEach((key, index) => {
      tns[index].children = []
      return _loop(__level, key, tns[index].children)
    })
  }
  _loop(z)
  return gData
}
export function calcTotal (x = 3, y = 2, z = 1) {
  /* eslint no-param-reassign:0*/
  const rec = (n) => n >= 0 ? x * Math.pow(y, n--) + rec(n) : 0
  return rec(z + 1)
}
console.log('总节点数（单个tree）：', calcTotal())
// 性能测试：总节点数超过 2000（z要小）明显感觉慢。z 变大时，递归多，会卡死。

export const gData = generateData()

function isPositionPrefix (smallPos, bigPos) {
  if (bigPos.length < smallPos.length) {
    return false
  }
  // attention: "0-0-1" "0-0-10"
  if ((bigPos.length > smallPos.length) && (bigPos.charAt(smallPos.length) !== '-')) {
    return false
  }
  return bigPos.substr(0, smallPos.length) === smallPos
}
// console.log(isPositionPrefix("0-1", "0-10-1"));

// arr.length === 628, use time: ~20ms
export function filterParentPosition (arr) {
  const levelObj = {}
  arr.forEach((item) => {
    const posLen = item.split('-').length
    if (!levelObj[posLen]) {
      levelObj[posLen] = []
    }
    levelObj[posLen].push(item)
  })
  const levelArr = Object.keys(levelObj).sort()
  for (let i = 0; i < levelArr.length; i++) {
    if (levelArr[i + 1]) {
      levelObj[levelArr[i]].forEach(ii => {
        for (let j = i + 1; j < levelArr.length; j++) {
          levelObj[levelArr[j]].forEach((_i, index) => {
            if (isPositionPrefix(ii, _i)) {
              levelObj[levelArr[j]][index] = null
            }
          })
          levelObj[levelArr[j]] = levelObj[levelArr[j]].filter(p => p)
        }
      })
    }
  }
  let nArr = []
  levelArr.forEach(i => {
    nArr = nArr.concat(levelObj[i])
  })
  return nArr
}
// console.log(filterParentPosition(
//   ['0-2', '0-3-3', '0-10', '0-10-0', '0-0-1', '0-0', '0-1-1', '0-1']
// ));

function loopData (data, callback) {
  const loop = (d, level = 0) => {
    d.forEach((item, index) => {
      const pos = `${level}-${index}`
      if (item.children) {
        loop(item.children, pos)
      }
      callback(item, index, pos)
    })
  }
  loop(data)
}

function spl (str) {
  return str.split('-')
}
function splitLen (str) {
  return str.split('-').length
}

export function getFilterExpandedKeys (data, expandedKeys) {
  const expandedPosArr = []
  loopData(data, (item, index, pos) => {
    if (expandedKeys.indexOf(item.key) > -1) {
      expandedPosArr.push(pos)
    }
  })
  const filterExpandedKeys = []
  loopData(data, (item, index, pos) => {
    expandedPosArr.forEach(p => {
      if ((splitLen(pos) < splitLen(p) &&
        p.indexOf(pos) === 0 || pos === p) &&
        filterExpandedKeys.indexOf(item.key) === -1) {
        filterExpandedKeys.push(item.key)
      }
    })
  })
  return filterExpandedKeys
}

function isSibling (pos, pos1) {
  pos.pop()
  pos1.pop()
  return pos.join(',') === pos1.join(',')
}

export function getRadioSelectKeys (data, selectedKeys, key) {
  const res = []
  const pkObjArr = []
  const selPkObjArr = []
  loopData(data, (item, index, pos) => {
    if (selectedKeys.indexOf(item.key) > -1) {
      pkObjArr.push([pos, item.key])
    }
    if (key && key === item.key) {
      selPkObjArr.push(pos, item.key)
    }
  })
  const lenObj = {}
  const getPosKey = (pos, k) => {
    const posLen = splitLen(pos)
    if (!lenObj[posLen]) {
      lenObj[posLen] = [[pos, k]]
    } else {
      lenObj[posLen].forEach((pkArr, i) => {
        if (isSibling(spl(pkArr[0]), spl(pos))) {
          // 后来覆盖前者
          lenObj[posLen][i] = [pos, k]
        } else if (spl(pkArr[0]) !== spl(pos)) {
          lenObj[posLen].push([pos, k])
        }
      })
    }
  }
  pkObjArr.forEach((pk) => {
    getPosKey(pk[0], pk[1])
  })
  if (key) {
    getPosKey(selPkObjArr[0], selPkObjArr[1])
  }

  Object.keys(lenObj).forEach((item) => {
    lenObj[item].forEach((i) => {
      if (res.indexOf(i[1]) === -1) {
        res.push(i[1])
      }
    })
  })
  return res
}