流星Collection.find使用變量作爲動態蒙戈查詢字段

Question

我想在Collection.find查詢中使用一個變量作爲字段說明，但只是山雀忽略它

var qry = "{\"" + field_name + "\":" + field_value + "}" 
    console.log(qry)// {"customer_active":true} 
    Customers.find(qry).map(function(customer){// doesn't find anything 
     console.log(customer) 
     var groups = customer.customer_group_id.push(a._id) 

     Customers.update({$set: {customer_group_id: groups}}) 
    }) 

如何建立一個動態查詢

Answer 1

qry需要是一個對象，而不是一個字符串。因此，建立像這樣代替：

var qry = {}; 
qry[field_name] = field_value; 

Answer 2

我包裹查詢在JSON.parse的伎倆

var qry = "{\"" + field_name + "\":" + field_value + "}" 
    console.log(JSON.parse(qry)) 
    Customers.find(JSON.parse(qry)).map(function(customer){ 
     console.log(customer) 
     var groups = customer.customer_group_id.push(a._id) 

     Customers.update({$set: {customer_group_id: groups}}) 
    })