Laravel 更新时如何忽略特定字段的唯一性验证

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\Hash;
use Illuminate\Validation\Rule; // 引入 Rule 类，用于更复杂的验证场景

use Auth;
use DB;

use App\Models\User;
use App\Models\Button;
use App\Models\Link;


class UserController extends Controller
{
    // ... 其他方法 ...

    /**
     * 显示用户页面编辑表单
     * @param Request $request
     * @return \Illuminate\View\View
     */
    public function showPage(request $request)
    {
        $userId = Auth::user()->id;

        $data['pages'] = User::where('id', $userId)->select('littlelink_name', 'littlelink_color', 'littlelink_fontcolor', 'littlelink_pixiv', 'littlelink_description')->get();

        return view('/studio/page', $data);
    }

    /**
     * 保存用户页面设置（名称、描述、图片等）
     * @param Request $request
     * @return \Illuminate\Http\RedirectResponse
     */
    public function editPage(request $request)
    {
        // 1. 在验证规则定义前获取当前用户ID
        $userId = Auth::user()->id; 

        $request->validate([
            'image' => 'nullable|mimes:jpeg,jpg,png|max:100',
            // 修正后的 unique 规则：忽略当前用户ID的记录
            'pageName' => [
                'nullable',
                'alpha_dash',
                Rule::unique('users', 'littlelink_name')->ignore($userId),
            ],
            'pageColor' => 'nullable',
            'pageFontcolor' => 'nullable',
            'pageDescription' => 'nullable|regex:/^[\w.\- ]+$/i',
            'pagePixiv' => 'nullable|url',
        ]);

        // 获取当前用户的 littlelink_name，用于文件命名
        $littlelink_name = Auth::user()->littlelink_name;

        $profilePhoto = $request->file('image');
        $pageName = $request->pageName;
        $pageColor = $request->pageColor;
        $pageFontcolor = $request->pageFontcolor;
        $pageDescription = $request->pageDescription;
        $pagePixiv = $request->pagePixiv;

        // 更新用户页面信息
        User::where('id', $userId)->update([
            'littlelink_name' => $pageName, 
            'littlelink_color' => $pageColor, 
            'littlelink_fontcolor' => $pageFontcolor, 
            'littlelink_pixiv' => $pagePixiv, 
            'littlelink_description' => $pageDescription
        ]);

        // 处理图片上传
        if(!empty($profilePhoto)){
            $profilePhoto->move(public_path('/img'), $littlelink_name . ".png");
        }

        return back()->with('message', 'Saved');
    }

    // ... 其他方法 ...
}