使用mgo通过输入选择查询的选定字段

Question

Is it possible to have a method that takes as input an array of strings and then use this array to create the selected fields of a query? So if you have lets say this array:

var myArray []string{"fieldA","fieldB"}

Then you can create this automatically:

selectedFields := bson.M{"fieldA": 1, "fieldB": 1}

and then execute the query

result = c.Find(query).Select(selectedFields).One()

Answer 1

You can use something like:

func sel(q ...string) (r bson.M) {
    r = make(bson.M, len(q))
    for _, s := range q {
        r[s] = 1
    }
    return
}

result := c.Find(query).Select(sel("fieldA", "fieldB")).One() 
// or 

fields := []string{"fieldA","fieldB"}
result := c.Find(query).Select(sel(fields...)).One()