Unexpected token , - asp value showing as undefined - javascript

i am trying to upload some data from vb.net to asp.net using array json.
my code:
<script type="text/javascript">
$(function() {
var a = $("#hidden").val();
var array = JSON.parse(a);
however, when i debugged this on the browser, "a" and "array" was showing as undefined. even though in the code behind it was showing the value..
after further investigation, i found out that if it is like this it works:
var a = "[1, 2, 3]";
var array = JSON.parse(a);
note it is showing as a string, however when i take the string of:
var a = [1, 2, 3];
var array = JSON.parse(a);
it says its undefined - Uncaught SyntaxError: Unexpected token, am guessing its to do with the JSON.
now back to my code and my error:
code behind (vb)
Dim array As New ArrayList
For Each row In ChartData.Rows
array.Add(row("Day"))
Next row
Dim serializer As New JavaScriptSerializer()
Dim arrayJson As String = serializer.Serialize(array)
hidden.Value = arrayJson
and code in asp.
<asp:HiddenField ID="hidden" runat="server" />
var a = $("#hidden").val();
var array = JSON.parse(a);
my problem is, why is it showing undefined! what have i done wrong.
thanks


on asp.net the rendered id is not the one you use on code behind, to get it on page you need to use the ClientID as:
var a = $("#<%=hidden.ClientID%>").val();


Json.parse takes a string and returns a json object. It needs a valid json input in order to parse the input, this is a string. You can also use the JSON.stringify method before call parse to ensure passing an input as a string.

Related

C# JSON String returned in ambiguous format

i have an issue with my logged Json String as it replaces the double quotes with "
Controller Code :
var message = new SuccessMessagesVM()
{
Title = successMessageType == (int)EnumHelper.SuccessMessageTypes.Add ? "It's beautiful" : CustomModel.Resources.SuccessMessagesResources.EditFormSuccess,
Message = successMessageType == (int)EnumHelper.SuccessMessageTypes.Add ? CustomModel.Resources.SuccessMessagesResources.AddFormSuccess : CustomModel.Resources.SuccessMessagesResources.EditFormSuccess,
ColorCode = (int)EnumHelper.MessagesCodes.Success
};
var json = JsonConvert.SerializeObject(message);
ViewBag.SuccessMessage = successMessageType == 0 ? null : json;
Javascript just logs the ViewBag.SuccessMessage as following:
console.log('#ViewBag.SuccessMessage');
and the object is displayed as {"Message":"تم إضافة النموذج بنجاح","Title":"It's beautiful","ColorCode":3}
replacing all single quotes with ' and all double quotes with "
I expect the output to be {"Message":"تم إضافة النموذج بنجاح","Title":"It's beautiful","ColorCode":3}

This is because you are using ViewBag variable.
In order to use ViewBag, you can write it as followed:
First, in view:
#{
var jss = new System.Web.Script.Serialization.JavaScriptSerializer();
var successMessageJson = jss.Serialize(ViewBag.SuccessMessage);
}
Then use it:
<script>
//use Json.parse to convert string to Json
var successMessageInfo = JSON.parse('#Html.Raw(successMessageJson)');
</script>

There's a few different issues and a few different approaches, and the OP doesn't give us any view code, so it's a bit of guesswork.
My feeling is that you should just return the SuccessMessagesVM from your method, and access the properties individually in your view (probably using #Html.DisplayFor and HTML). This will ensure that any redundant quotation marks are never created in the first place, and will give you total control over how the values are displayed.
You should not expect console.log(#ViewBag.Anything) to display properly. If you need the data as a JavaScript object, don't stick it in the ViewBag, as it will get rendered as HTML.
If you must write to a JavaScript object you can, but it begs the question why are you not using an ajax request if all you want is data?

Get values from JSON returned data

So I have a function that makes an ajax call and returns a json string. I am having trouble trying to access the values that I need, below is my code of what I have and a few examples of what I have tried.
s.search().then(function (specials) {
var returnJSON = JSON.parse(specials[0]);
var x = returnJSON.location.x;
var y = returnJSON.location.y;
});
When I check the dev tools I'm getting the following error.
JSON.parse: unexpected character at line 1 column 2 of the JSON data
Here is the the JSON returned value after I stringify it.
[{"feature":{"geometry":{"type":"point","x":-82.9172080701955,"y":42.55426092899978,"spatialReference":{"wkid":102100,"latestWkid":3857}},"symbol":null,"attributes":{"Addr_type":"Postal","Match_addr":"48035, Clinton Township, Michigan","StAddr":"","City":"Clinton Township","score":100},"infoTemplate":null},"extent":{"type":"extent","xmin":-82.922209,"ymin":42.549261,"xmax":-82.912209,"ymax":42.559261,"spatialReference":{"wkid":102100,"latestWkid":3857}},"name":"48035, Clinton Township, Michigan"},{"feature":{"geometry":{"type":"point","x":-84.03589825899667,"y":44.826904141314174,"spatialReference":{"wkid":102100,"latestWkid":3857}},"symbol":null,"attributes":{"Addr_type":"Locality","Match_addr":"Clinton Twp, Michigan","StAddr":"","City":"Clinton Twp","score":100},"infoTemplate":null},"extent":{"type":"extent","xmin":-84.085899,"ymin":44.776904,"xmax":-83.985899,"ymax":44.876904,"spatialReference":{"wkid":102100,"latestWkid":3857}},"name":"Clinton Twp, Michigan"},{"feature":{"geometry":{"type":"point","x":-83.93987906956261,"y":42.065412162742234,"spatialReference":{"wkid":102100,"latestWkid":3857}},"symbol":null,"attributes":{"Addr_type":"Locality","Match_addr":"Clinton Twp, Michigan","StAddr":"","City":"Clinton Twp","score":100},"infoTemplate":null},"extent":{"type":"extent","xmin":-83.98988,"ymin":42.015412,"xmax":-83.88988,"ymax":42.115412,"spatialReference":{"wkid":102100,"latestWkid":3857}},"name":"Clinton Twp, Michigan"},{"feature":{"geometry":{"type":"point","x":-82.93354923650725,"y":42.60054198222781,"spatialReference":{"wkid":102100,"latestWkid":3857}},"symbol":null,"attributes":{"Addr_type":"Locality","Match_addr":"Clinton Twp, Michigan","StAddr":"","City":"Clinton Twp","score":100},"infoTemplate":null},"extent":{"type":"extent","xmin":-82.98355,"ymin":42.550542,"xmax":-82.88355,"ymax":42.650542,"spatialReference":{"wkid":102100,"latestWkid":3857}},"name":"Clinton Twp, Michigan"},{"feature":{"geometry":{"type":"point","x":-83.97095926895429,"y":42.07240087260328,"spatialReference":{"wkid":102100,"latestWkid":3857}},"symbol":null,"attributes":{"Addr_type":"Locality","Match_addr":"Clinton, Michigan","StAddr":"","City":"Clinton","score":94.29},"infoTemplate":null},"extent":{"type":"extent","xmin":-84.02096,"ymin":42.022401,"xmax":-83.92096,"ymax":42.122401,"spatialReference":{"wkid":102100,"latestWkid":3857}},"name":"Clinton, Michigan"},{"feature":{"geometry":{"type":"point","x":-84.6015125489642,"y":42.943655651388326,"spatialReference":{"wkid":102100,"latestWkid":3857}},"symbol":null,"attributes":{"Addr_type":"SubAdmin","Match_addr":"Clinton, Michigan","StAddr":"","City":"Clinton","score":94.29},"infoTemplate":null},"extent":{"type":"extent","xmin":-84.839514,"ymin":42.705656,"xmax":-84.363514,"ymax":43.181656,"spatialReference":{"wkid":102100,"latestWkid":3857}},"name":"Clinton, Michigan"}]
I am trying to access candidates location x value and y value.

There are some Strings in your JSON on separate lines. When you copy and paste your JSON in a linter (e.g.: json linter), you will see the errors.
EDIT:
You edited your question so you are now using valid JSON.
There is no need to parse your JSON when you already have valid JSON. You can just select the correct keys. Looking at your JSON, you can select your x and y like this:
var returnJSON = specials[0];
var x = returnJSON.feature.geometry.x;
var y = returnJSON.feature.geometry.y;
Checkout this codepen for an example.

You don't need to "parse" JSON returned from a service usually. It is already a Javascript object in the then callback.
s.search().then(function (specials) {
var firstItem = specials[0];
var x = firstItem.location.x;
var y = firstItem.location.y;
});
It should be noted, however, that the first item that comes back in your array of specials does not have a property location accoring to the JSON example you posted.
Perhaps you were after firstItem.feature.geometry.x, but im not sure.

Getting return value from JavaScript in UIWebView

I want to fetch JavaScript return value in my ViewController,
The problem is that, if there is small amount of data like String, I'm getting it.
But if there is large data like JSON object,It's showing nil.
When I call same JS function in Safari > Develop > iOS simulator, it's giving JSON object after 1-2 secs.
Here is my code:
var value = IBwebView.stringByEvaluatingJavaScriptFromString("get_small_string()")
println(value) //Printing value
but this prints nil,
var value = IBwebView.stringByEvaluatingJavaScriptFromString("get_JSON()")
println(value) //Printing nil
anyone knows how can I fetch big size JS return value in iOS object?

This solve my problem,
var value = IBwebView.stringByEvaluatingJavaScriptFromString("get_JSON()")
var err:NSError?
var obj:AnyObject? = NSJSONSerialization.JSONObjectWithData(value!.dataUsingEncoding(NSUTF8StringEncoding)!, options:nil, error:&err)
if let items = obj as? NSDictionary {
var data1:String = items.objectForKey("data1") as? String
var data2:String = items.objectForKey("data2") as? String
var data3:String = items.objectForKey("data3") as? String
}

As soon as you will return an object it will not work, what you can try instead is to return a stringified version of your object
JSON.stringify(yourObject);
And parse this string on the native side.

If your java script method "get_JSON()" return more than 10 MB data then its not allowed by stringByEvaluatingJavaScriptFromString method.
Or If it take more than 10 sec to process output ,in that case you will be get nil value as output.

How to properly decode a JSON string encoded using Html.Raw(Json.Encode(Model))?

I am encoding some model data into a html element like this:
#Html.Raw(Json.Encode(Model));
The json string returned looks like this:
{"TestList":[{"FrequencyType":"1X","GCDs":"585.6","Identifier":"6144","SeqNo":9306,"SeqNoSpecified":true,"TSeqNo":8314,"TSeqNoSpecified":true,"TestDescr":"HBsAg"},{"FrequencyType":"1X","GCDs":"585.6","Identifier":"6124","SeqNo":9295,"SeqNoSpecified":true,"TSeqNo":8315,"TSeqNoSpecified":true,"TestDescr":"HCV Ab"},{"FrequencyType":"1X","GCDs":"585.3","Identifier":"6","SeqNo":9729,"SeqNoSpecified":true,"TSeqNo":8309,"TSeqNoSpecified":true,"TestDescr":"HD Monthly LS"}],"Frequency":[{"Key":"ANNUAL","Value":"Annually"},{"Key":"BIMONTH","Value":"Bi-Monthly"},{"Key":"BIWEEK","Value":"Bi-Weekly"},{"Key":"MON","Value":"Monthly"},{"Key":"1X","Value":"One Time"},{"Key":"QTR","Value":"Quarterly"},{"Key":"SMAN","Value":"Semi-Annual"},{"Key":"WEEK","Value":"Weekly"}]};
When I try to parse this using JSON.parse, I get an error:
arrayTestList = [];
var jsonTestList = $('#TestList').text();
jsonTestList = JSON.stringify(jsonTestList);
arrayTestList = JSON.parse(jsonTestList);
alert(arrayTestList.TestList[0]); // <===== this line is failing
Unable to get value of the property '0': object is null or undefined
How do I convert this jsonTestList string into a javascript array so that I can access elements of arrayTestList properly?
Edit:
Sorry, I forgot to mention my edit. Basically above javascript code is inside a Partial View 2. The code where I am json encoding the model is in another Partial View 1. From P V 2, I cannot access the model object of P V 1, so I am just dumping the contents into a div tag, so that I can access this list TestList element.

Try removing this line:
jsonTestList = JSON.stringify(jsonTestList);
jsonTestList is already a JSON string

The issue is now resolved.
I was getting an invalid character, but couldn't immediately recognize which character it was that was causing the problem. I found that my JSON string isn't valid because of the trailing semicolon that was output by the Json.Encode method. I validated the JSON string # http://jsonlint.com.
Once I removed that semicolon, the json string is populated as a JavaScript array into arrayTestList object.
Now just this works, as mentioned in both the answers above, JSON.stringify is not needed.
var arrayTestList = [];
var jsonTestList = $('#TestList').text().replace(";","");
arrayTestList = JSON.parse(jsonTestList);
alert(arrayTestList.TestList[0]);

Why are you using Json.Encode? Also in your code, why are you writing redundant code first you are using JSON.stringify and the JSON.parse same object.
jsonTestList = JSON.stringify(jsonTestList);
arrayTestList = JSON.parse(jsonTestList);
As per my understanding just Html.Raw will work
In JavaScript
var jsonObject = #Html.Raw(Model.TestList); //Here you will get JavaScript Object
var jsonTestList = jsonObject.TestList;

convert an input value in array

I have this data in an input: [16,57.35], [23,56.26], [34,54.57]
and I want to turn it into an array
var data =$('#data').val();
var array = JSON.parse ("["+data+"]");
I'm having this error
Uncaught SyntaxError: Unexpected token.
How I can fix it or I can convert the input value in array?

Your code is working check it here, you may need to include required jQuery library or check some thing else in the code causing it.
data = $('#txt1').val();
arr = JSON.parse ("["+data+"]");
console.log(arr);

Try using the eval function:
var data = "123, 456, 789";
var array = eval("[" + data + "]");
You'll need to make sure that whatever you're inputting is valid JSON, but the above code will output an array for you. Hope it helps.

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