动态访问数组对象

Question

I have below array and trying to access the array objects based on key dynamically but its not giving me the exact object details ,I am getting table1/table2 values dynamically and based on that i am trying to get the table details

var arr = [{"table1":{"tablename":"table1","tablecolumns":"no","patternCheckStatus":"true","columns":[{"columnname":"DescriptionGovt","datatype":"AlphaNumeric","patternregex":"(lll);;;"},{"columnname":"GovtGrant","datatype":"Alphabetic","patternregex":"(lkkll)"}]}},{"table2":{"tablename":"table2","tablecolumns":"no","patternCheckStatus":"false","columns":[{"columnname":"DateItem","datatype":"LowerCase","patternregex":"(3rdtable)hhhh"}]}}]

var id = table1;
console.log("obj " + JSON.stringify(arr[0].id));

i am getting undefined in console and i change the id with actual key name i am getting the object details.. console.log("obj "+ JSON.stringify(arr[0].table1));

Answer 1

尝试这个。

var id = 'table1'; console.log("obj " + JSON.stringify(arr[0][id]));

Answer 2

this will work ==>

var id ="table1";
console.log(" obj = "+JSON.stringify(arr[0][id]));

or

console.log(" obj = "+arr[0].table1);

in the first example, you are treating your object as a json by stringify it & in the second we are using it as POJO.

Answer 3

Instead of arr[0].id , use arr[0][id] .

• arr[0].id is equivalent to accessing the id field from the first element of the array arr
• arr[0][id] is equivalent to accessing the field ${id} (ie the field which has the key, value of the id variable) from the first element of the array arr