Angular Firestore根据条件更改此查询

Question

如何根据条件更改此查询

let query = (ref: CollectionReference)=>{
return ref.where("dateOrd", ">=", this.dateIn)
.where("dateOrd", "<=", this.dateOu)
.where("status", "==", this.staTus)
.where("seller", "==", this.idseller)  
.where("ptype", "in", this.ptype)
.orderBy("dateOrd", "desc")
.orderBy("creado", "desc")
.limit(5000)
}

例如，如果满足条件，则更改查询

类似的东西(此操作失败(

if (typeof this.idCli!="undefined"){
query = query.where("client", "==", this.idCli)
}

但是，我该如何进行多重查询？

请帮帮我。谢谢

Answer 1

Firestore查询遵循生成器模式，其中对where()的每次调用都返回一个新查询。

所以你只需重复呼叫where，就像在你的第二个片段：中一样

let query = (ref: CollectionReference)=>{
let q = ref.where("dateOrd", ">=", this.dateIn)
.where("dateOrd", "<=", this.dateOu)
.where("status", "==", this.staTus)
.where("seller", "==", this.idseller)  
.where("ptype", "in", this.ptype)
.orderBy("dateOrd", "desc")
.orderBy("creado", "desc")
.limit(5000)
if (typeof this.idCli!="undefined"){
q = q.where("client", "==", this.idCli)
}
return q;
}

如果你的其他条件也是动态的，你可以对它们做同样的事情：

let q = ref;
if (typeof this.dateIn!="undefined"){
q = q.where("dateOrd", ">=", this.dateIn)
}
if (typeof this.dateOu!="undefined"){
q = q.where("dateOrd", "<=", this.dateOu)
}
...
q = q.limit(5000)
if (typeof this.idCli!="undefined"){
q = q.where("client", "==", this.idCli)
}
return q;