Typeahead search suggestions undefined - Remote Ajax

Question

I am trying to make the typeahead remote source to a web method which will be repsond with results in JSON format.

Ajax is getting success and it;s returing the results properly . The console in the below code will print like below

[{"Id":"1","Value":"Midhun"},{"Id":"2","Value":"Midhun2"}]

But the typeahead suggestions are all undefined

var typeHeadEngine = new Bloodhound({ name: 'Name', remote: { url: 'page.aspx/method',

        ajax: {
            type: "POST",
            data: JSON.stringify({ "query": '%QUERY' }),
            contentType: "application/json; charset=utf-8",
            dataType: "text",                
            success: function (data) {
                var obj = JSON.parse(data);
                console.log(obj.d);
                return obj.d;
            }

        }

    },
    datumTokenizer: function (d) {
        return Bloodhound.tokenizers.whitespace(d.val);
    },
    queryTokenizer: Bloodhound.tokenizers.whitespace
});

typeHeadEngine .initialize();

$('.typeahead').typeahead({
    hint: true,
    highlight: true,

    minLength: 3
},   {
  name: 'Name',
  displayKey: 'Value',
  source: typeHeadEngine.ttAdapter()

});

Web method is returing JSON string which am converting to array in the ajax success function. During googling i found that typeahead requires array and not JSON object ,so I am converting into array.

i went through plently of similar questions to figure it out. But i am unable to do so ,
Can anyone please help to figure out what i am doing wrong here ?

Answer 1

You should not use the success field of the ajax options to transform your JSON, instead you have to use the filter field provided by Bloodhound:

var typeHeadEngine = new Bloodhound({
name: 'Name',
remote: {
    url: 'page.aspx/method',
    ajax: {
        type: "POST",
        data: JSON.stringify({
            "query": '%QUERY'
        }),
        contentType: "application/json; charset=utf-8",
        dataType: "text"
    },
    filter: function (data) {
        var obj = JSON.parse(data);
        console.log(obj.d);
        return obj.d;
    }
},
datumTokenizer: function (d) {
    return Bloodhound.tokenizers.whitespace(d.val);
},
queryTokenizer: Bloodhound.tokenizers.whitespace
});