feat: back top #ASM-14132

.changeset/cold-schools-sit.md

@@ -0,0 +1,5 @@
+---
+'@alauda/ui': patch
+---
+
+back to top time optimization

src/back-top/back-top.component.ts

@@ -88,10 +88,31 @@ export class BackTopComponent {
   }
 
   handleClick(event: Event) {
-    this._scrollTarget.scrollTo({ top: 0, behavior: 'smooth' });
+    this.scrollToTop(300);
     this.click.emit(event);
   }
 
+  scrollToTop(duration: number) {
+    const startHeight = this.getTargetScrollTop(this._scrollTarget);
+    let startTime: number;
+
+    const scrollStep = (timestamp: number) => {
+      if (!startTime) {
+        startTime = timestamp;
+      }
+      const scrollHeight = Math.max(
+        startHeight - ((timestamp - startTime) / duration) * startHeight,
+        0,
+      );
+
+      this._scrollTarget.scrollTo(0, scrollHeight);
+      if (scrollHeight) {
+        requestAnimationFrame(scrollStep);
+      }
+    };
+    requestAnimationFrame(scrollStep);
+  }
+
   getTarget(target: TargetType): Element | Window {
     const scrollTarget =
       (typeof target === 'string' && document.querySelector(target)) ||