初始化

ebts-ui/src/views/tool/top/utils/index.js

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+/**
+ * Created by clay on 2019/10/14
+ * Description: common utils
+ */
+
+/**
+ * This is just a simple version of deep copy
+ * Has a lot of edge cases bug
+ * If you want to use a perfect deep copy, use lodash's _.cloneDeep
+ * @param {Object} source
+ * @returns {Object} targetObj
+ */
+export function deepClone(source) {
+  if (!source && typeof source !== 'object') {
+    throw new Error('error arguments: deepClone')
+  }
+  let targetObj = source.constructor === Array ? [] : {}
+  Object.keys(source).forEach(key => {
+    if (source[key] && typeof source[key] === 'object') {
+      targetObj[key] = deepClone(source[key])
+    } else {
+      targetObj[key] = source[key]
+    }
+  })
+  return targetObj
+}
+
+/**
+ * Randomly extract one or more elements from an array
+ * If you want to use a perfect solution, use lodash's _.sample or _.sampleSize
+ * @param {Array} arr
+ * @param {number} count
+ * @returns {Array} arr
+ */
+export function getRandomArrayElements(arr, count = 1) {
+  if (count > arr.length) {
+    throw new Error('error arguments: count is greater than length of array')
+  }
+  let shuffled = arr.slice(0), i = arr.length, min = i - count, temp, index
+  while (i-- > min) {
+    index = Math.floor((i + 1) * Math.random())
+    temp = shuffled[index]
+    shuffled[index] = shuffled[i]
+    shuffled[i] = temp
+  }
+  return shuffled.slice(min)
+}