一个键在多个相同类型结构上的一致性映射是否可能？

Question

我正在尝试将一个地址映射到属于同一地址的多个相同类型的结构。如果之后我想根据请求为一个地址选择任何 "stored" 结构，我该怎么做？

我创建了一个名为 Prescription 的结构，以及一个与患者地址的映射。所以我真正想要的是将患者地址映射到几个处方结构。

struct Prescription {
    address patients_address;
    string medicament;
    string dosage_form;
    uint amount;
    uint date;
}

mapping (address => Prescription) ownerOfPrescription;

address [] public patients;

function createPrescription(address patients_address, string medicament, string dosage_form, uint amount, uint date) public restricted {
    var newPrescription = ownerOfPrescription[patients_address];

    newPrescription.medicament = medicament;
    newPrescription.dosage_form = dosage_form;
    newPrescription.amount = amount;
    newPrescription.date = date;

    patients.push(patients_address) -1;
}

function getPre(address _address)view public returns (string, string, uint, uint){ 
    return( 
        ownerOfPrescription[_address].medicament, 
        ownerOfPrescription[_address].dosage_form, 
        ownerOfPrescription[_address].amount, 
        ownerOfPrescription[_address].date);
}

现在我会有一个功能，我可以调用一个病人的所有书面处方。其实我只能叫一个地址的最后一张处方。

Answer 1

当然，a mapping 的值类型可以是数组：

// map to an array
mapping (address => Prescription[]) ownerOfPrescription;

function createPrescription(...) ... {
     // add to the end of the array
     ownerOfPrescription[patients_address].push(Prescription({
         medicament: medicament,
         ...
     });

     patients.push(patients_address);
}