Question

我在变量$types中有以下结果集;我有第二个变量$typeid，目前的值为11。

[
    {"_id":"54077696dee5bd6ce0000029","typeID":"2","type":"road"},
    {"_id":"54077696dee5bd6ce000002a","typeID":"3","type":"street"},
    {"_id":"54077696dee5bd6ce000002b","typeID":"4","type":"avenue"},
    {"_id":"54077696dee5bd6ce000002c","typeID":"5","type":"place"},
    {"_id":"54077696dee5bd6ce000002d","typeID":"6","type":"drive"},
    {"_id":"54077696dee5bd6ce000002e","typeID":"7","type":"way"},
    {"_id":"54077696dee5bd6ce000002f","typeID":"8","type":"blvd"},
    {"_id":"54077696dee5bd6ce0000030","typeID":"9","type":"court"},
    {"_id":"54077696dee5bd6ce0000031","typeID":"10","type":"lane"},
    {"_id":"54077696dee5bd6ce0000032","typeID":"11","type":"mile"}
]

我想在不使用type的情况下检索相应的mile（@for loop）。我尝试使用以下内容：

{{ 
    $types->filter(function($t) use ($typeid) { 
        return $t->typeID == $typeid; 
    })->type 
}}

但我收到错误：

Undefined property: Illuminate\Database\Eloquent\Collection::$type

因为$types->filter(function($t) use($typeid) { return $t->typeID == $typeid; })返回以下内容（我认为"9"是上面数组中的索引...不能保证记录将保持给定的顺序）：

{"9":{"_id":"54077696dee5bd6ce0000032","typeID":"11","type":"mile"}}

我期待{"_id":"54077696dee5bd6ce0000032","typeID":"11","type":"mile"}。有没有办法重写->filter方法，以便它可以返回：

{"_id":"54077696dee5bd6ce0000032","typeID":"11","type":"mile"}
//or
[{"_id":"54077696dee5bd6ce0000032","typeID":"11","type":"mile"}]  //?

或者，有没有办法写行，以便我得到所需的结果：例如以11开头并获得里程。

Answer 1

在不知道你如何查询收藏品的情况下，很难说。假设您正在使用名为Type的Eloquent模型。执行此操作的最佳方法是在模型中创建查询范围。

$types = Type::ofTypeId($typeid)->get();

在您的模型中，您将添加以下功能：

public function scopeOfTypeId($query, $typeid)
{
    return $query->whereTypeID($typeid);
}

Answer 2

文档中有一条注释，直到现在才有意义：

注意：过滤集合并将其转换为JSON时，请尝试首先调用values函数来重置数组的键。

因此，如下重写该行可以解决问题：

{{ 
    $types->filter(function($t) use ($typeid) { 
        return $t->typeID == $typeid; 
    })->values()[0]->type 
}}

由于$types->filter(function($t) use ($typeid) { return $t->typeID == $typeid; })->values()的值为：

[{"_id":"54077696dee5bd6ce0000032","typeID":"11","type":"mile"}]

Laravel 4 - 过滤集合

2 个答案: