Question

如何将函数logic传递给find函数以便在每个文档上使用它？

我试图用属性中的某些值递归地查找Mongo文档。我已经定义了一个“算法”，并希望这个find - 函数，但尽管阅读了查询，搜索和find()，我没有运气。

// match every node with propertyname "Reference" with the exact value "43_1"
var logic = function(currentKey, currentValue) {
    return ( currentKey == "Reference" && currentValue === "43_1" );
};

db.getCollection('metavalg').find(function() {  
    function recurSearchObj(doc) {
        return Object.keys(doc).some(function(key) {
            if ( typeof(doc[key]) == "object" && doc[key] !== null ) {
                return recurSearchObj(doc[key]);
            } else {
                // invoke matching-logic
                return logic(key, doc[key]);
            }
        });
    }
    // search document recursively 
    return recurSearchObj(this);
})

在弗拉基米尔M的帮助下，我最终重新编写代码并执行此操作：

db.getCollection('metavalg').find(function() {  
    function inspectObj(doc, logic) {
        return Object.keys(doc).some(function(key) {
            if ( typeof(doc[key]) == "object" && doc[key] !== null ) {
                return inspectObj(doc[key], logic);
            } else {
                return logic(key, doc[key]);
            }
        });
    }
    return inspectObj(this, function(currentKey, currentValue) {
        return ( currentKey == "Nummer" && currentValue === "43_1" );
        //return ( currentKey == "Navn" && /max\.? 36/i.test(currentValue) );
    });
})

Answer 1

您可以将逻辑方法作为参数传递给recurcive搜索对象：

// match every node with propertyname "Reference" with the exact value "43_1"
var logic = function(currentKey, currentValue) {
    return ( currentKey == "Reference" && currentValue === "43_1" );
};

db.getCollection('metavalg').find(function() {  
    function recurSearchObj(doc, aLogic) {
        return Object.keys(doc).some(function(key) {
            if ( typeof(doc[key]) == "object" && doc[key] !== null ) {
                return recurSearchObj(doc[key], aLogic);
            } else {
                // invoke matching-logic
                if( aLogic(key, doc[key]) ){
                       // then do somthing 
                }
            }
        });
    }
    // search document recursively 
    return recurSearchObj(this, logic);
});

如何动态地为collection.find（）指定函数

1 个答案: