如何对相关表中的函数值求和？

Question

我有两个类：Share 和相关的EquityGrant

我在EquityGrant 中有这个数学函数

public function share() //relationship
{
    return $this->belongsTo(Share::class, 'share_id');
}
public function capitalCommitted() //my math function
{
    return $this->share_price * $this->shares_amount;
}

但是现在我需要返回我的capitalCommitted() 函数的Share 类总和，而我被卡住了。

我的Share班级：

public function grants() //relationship
{
    return $this->hasMany(EquityGrant::class);
}
public function totalIssued() //sum, works good
{
    return $this->grants->sum('shares_amount');
}
public function totalCommitted() //Stuck here
{
    //need help here, Must be like this: array_sum($this->grants->capitalCommitted());
}

Answer 1

使用这个：

public function getCapitalCommittedAttribute()
{
    return $this->share_price * $this->shares_amount;
}

public function totalCommitted()
{
    return $this->grants->sum('capitalCommitted');
}