新增获取随机颜色的方法

src/app/utils/color.ts

@@ -1,4 +1,9 @@
-export const ColorList: { bgColor: string, fontColor: string }[] = [
+export class Color {
+    bgColor: string;
+    fontColor: string
+}
+
+export const ColorList: Color[] = [
     {bgColor: '#7bcfa6', fontColor: '#000000'}, // 石青
     {bgColor: '#bce672', fontColor: '#000000'}, // 松花色
     {bgColor: '#ff8936', fontColor: '#000000'}, // 橘黄
@@ -7,3 +12,27 @@ export const ColorList: { bgColor: string, fontColor: string }[] = [
     {bgColor: '#3eede7', fontColor: '#000000'}, // 碧蓝
     {bgColor: '#177cb0', fontColor: '#ffffff'}, // 靛青
 ];
+
+export const ColorListLength = ColorList.length
+
+/**
+ * 获取一组随机颜色
+ * @param count 数量
+ */
+export function RandomColor(count: number = 1): Color[] {
+    const map = new Map<number, number>();
+    ColorList.forEach((color, index) => map.set(index, 0))
+    const colorArray: Color[] = [];
+    const oneRandomColor = () => {
+        const minValue = Math.min.apply(null, Array.from(map.values()))
+        const keys = Array.from(map.keys()).filter(key => map.get(key) === minValue);
+        const keyIndex = Math.floor(Math.random() * keys.length);
+        const index = keys[keyIndex];
+        map.set(index, minValue + 1);
+        return ColorList[index]
+    };
+    for (let i = 0; i < count; i++) {
+        colorArray.push(oneRandomColor());
+    }
+    return colorArray;
+}