php - Laravel - 当你有多对多关系时如何查询

Question

所以我有两个模型:Product 和 Size。一种产品可能有多种尺寸，一种尺寸可能有许多具有该尺寸的产品。我用 product_size 数据透视表在它们之间建立了很多关系。现在我需要查询所有具有一定尺寸的产品。这是我的代码:

编辑:

    $minPrice = $request['min'];
    $maxPrice = $request['max'];
    $colors = $request['color'];
    $sizes = $request['size'];

    if (count($request->all()) != 0) {

        $query = Product::with(['sizes' => function($query) use($request) {
            $sizeArray = $request->get('size');
            $query->whereIn('sizes.size', $sizeArray);
        }]);

        if(isset($minPrice) && isset($maxPrice)) {
            $query->whereBetween('price', array($minPrice, $maxPrice));
        }

        if(isset($colors)) {
            $query->whereIn('color_id', $colors);
        }

        $products = $query->get();
    }

这是我的模型:

class Product extends Model
{
    public function color()
    {
        return $this->belongsTo('App\Color');
    }

    public function sizes()
    {
        return $this->belongsToMany('App\Size', 'product_size')->withTimestamps();
    }
}

尺寸:

class Size extends Model
{
    public function products()
    {
        return $this->belongsToMany('App\Product', 'product_size')->withTimestamps();
    }
}

表格:

<form id="filterOptions" method="get" action="{{ URL::current() }}">
    <button type="submit" class="btn-color">Filter</button>

    <div class="clearfix space20"></div>
    <h5>Color</h5>
    <ul class="color-list">
        @foreach($availableColors as $color)
            <li><input type="checkbox" name="color[]" value="{{ $color->id }}"><a href="#"><span class="{{ $color->name }}"></span> {{$color->name_bg}}</a></li>
            {{ $color->name }}
        @endforeach
    </ul>
    <div class="clearfix space20"></div>

    <h5>Price</h5>
    <div id="slider-container"></div>
    <p>
        <span class="{{--pull-right--}} sc-range">
            <input class="pull-left" name="min" type="text" id="min" style="border: 0; color: #333333; font-weight: bold;"/>
            <input class="pull-right" name="max" type="text" id="max" style="border: 0; color: #333333; font-weight: bold;"/>
        </span>
    </p>

    <div class="clearfix space30"></div>
    <h5>Size</h5>
    <ul class="size-list">
        @foreach($availableSizes as $size)
            <li><input type="checkbox" name="size[]" value="{{ $size->id }}">{{ $size->size }}</li>
        @endforeach
    </ul>
</form>

这是我当前的代码。除了查询尺寸外，一切正常。它不输出任何错误。但是它不会根据尺寸查询产品。

Answer 1

您需要的是“Querying Relationship Existence”和whereIn() 的组合方法:

$products = Product::whereHas('size', function ($query) {
    // In the following line, replace "name" with the appropriate
    // field that relates to $request['size'].
    $query->whereIn('name', (array)$request['size']);
})->get();