feat(sys-server): add array util functions;

maslow · Sep 8, 2021 · b91ba2b · b91ba2b
1 parent 2789b0d
commit b91ba2b
Showing 1 changed file with 59 additions and 0 deletions.
diff --git a/packages/system-server/src/utils/array.ts b/packages/system-server/src/utils/array.ts
@@ -0,0 +1,59 @@
+
+/**
+ * Convert an array to map
+ * @param {Array} arr the original array
+ * @param {string} mapKey the key of map from object in array
+ * @param {boolean} unique if the value pointed by key is unique. default is true, if false given, the value will be an array
+ */
+export function array2map(arr: any[], mapKey: string, unique = true): any {
+  const map = {}
+  for (const el of arr) {
+    const key = el[mapKey]
+    if (unique) {
+      map[key] = el ?? null
+    } else {
+      map[key] = map[key] ?? []
+      map[key].push(el)
+    }
+  }
+  return map
+}
+
+/**
+ * Merge an map to an array by the value of `mapKey`
+ * @param {*} map the map object
+ * @param {*} arr target array
+ * @param {*} mapKey the map key to linked arr with map
+ * @param {*} as the new field key which will be inserted to target array
+ * @returns
+ */
+export function mergeMap2ArrayByKey(map: any, arr: any[], mapKey: string, as: string) {
+  as = as ?? mapKey
+
+  for (const el of arr) {
+    const key = el[mapKey]
+    el[as] = map[key]
+  }
+
+  return arr
+}
+
+/**
+ * Merge an map to an array by the values of `mapKey`
+ * @param {*} map the map object
+ * @param {*} arr target array
+ * @param {*} mapKey the map key to linked arr with map
+ * @param {*} as the new field key which will be inserted to target array
+ * @returns
+ */
+export function mergeMap2ArrayByKeyArray(map: any, arr: any[], mapKey: string, as: string) {
+  as = as ?? mapKey
+
+  for (const el of arr) {
+    const sub_arr = el[mapKey] || []
+    const rets = sub_arr.map(s => map[s])
+    el[as] = rets
+  }
+
+  return arr
+}