Web services can not return complete json

Question

0.00/5 (No votes)

See more:

I am developing an ASP.NET web application using web services and Ajax.
In web service, I have a method where I get data in Arabic, Urdu from the database and convert it into JSON But at the client-side, I didn't get the complete JSON format data which through an error in jquery of "JSON Parse".

For English my code work correctly, it only throws an error whenever there is some Arabic, Urdu data.

IN database I have the table named as "dd_diaryDetail"

What I have tried:

C#

object dta = null;
using (DD_db db = new DD_db())
{
db.Database.Connection.Open();
 var filval = filtervalue.Split(':');
string cmd = "SELECT * FROM dd_diaryDetail WHERE (tcs_id = @tcsid) AND (dd_date = @dt)";
dta = db.Database.SqlQuery<diarydetailview>(cmd, new SqlParameter("@tcsid", filval[0]),new SqlParameter("@dt", filval[1])).ToList();
if (dta != null)
{
db.Database.Connection.Close();
var res_data = js.Serialize(dta);
Context.Response.Clear();
Context.Response.ContentType = "application/json; charset=utf-8";
Context.Response.AddHeader("content-length", res_data.Length.ToString());
Context.Response.Write(res_data);
Context.Response.Flush();
}
db.Database.Connection.Close();
}

The result I get an incomplete JSON array

[{"dd_id":8,"tcs_id":8,"dd_date":"02-03-2020","CW_unitno":"44","CW_title":"ajdsaj","CW_pageno":"۳۳","CW_qno":"۸۸","CW_activity":"طگطگشدش","HW_unitno":"۷۷","HW_title":"چفچفچف","HW_pageno":"۷۷","HW_qno":"۹۹","HW_activity":"شفچففچففچفچ","Tst_unitno":"۵۵۵","Tst_title":"چفچفشش","Tst_pageno":"۴۴","Tst_qno":"۳۳","Tst_activity":"رچرچ"

Posted 2-Mar-20 7:36am

RASHID ALI786

Updated 3-Mar-20 2:50am

phil.o

v2

Add a Solution

Comments

[no name] 2-Mar-20 15:19pm

What kind of SQL Server are you using? Very strange to hit something like this these days...

2 solutions

Solution 1

There are multiple levels that you could be having the breakdown on this one; and it is going to take troubleshooting on your part to determine where the problem is.

1. After your EF query, what are the contents of dta? How many records are there versus how many should there be?

2. Inspect an individual instance of diarydetailview within dta. Is it complete? Repeat over a few and the instance which is throwing the issue.

3. Check and validate the content of res_data as well as the length.

Other things....

Did you know that you are closing the db.Connection twice if dta is populated?

What version of NET are you using? Apparently not all JSON serializers are the same:
Reference: c# - Serializing a list to JSON - Stack Overflow[^]

What browser are you using? And how are you calling your AJAX (jquery/ version)? This comes back to the data/length question above:
Reference: ajax - WCF service returns incorrect Content-Length when using gzip encoding - Stack Overflow[^]

Posted 2-Mar-20 11:28am

MadMyche

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard Deeming · Accepted Answer · 2020-03-03T02:50:00

Quote:

C#

Context.Response.AddHeader("content-length", res_data.Length.ToString());

This line is the problem.

The content length header specifies the number of bytes in the response body. You are sending the number of characters instead.

That mostly works when you send English text, because that only tends to use characters which can be represented as single bytes. But when you're returning characters which require multiple bytes to encode them, the string length will be less than the number of bytes.

UTF-8 - Wikipedia[^]

Most browsers will truncate the response body when it reaches the number of bytes specified in the content length header, which is why you're getting an incomplete response.

The simplest option would be to remove the line which sets the content length header. Otherwise, you're going to need to know exactly how many bytes you're sending:

C#

string res_data = js.Serialize(dta);
byte[] res_bytes = System.Text.Encoding.UTF8.GetBytes(res_data);

Context.Response.Clear();
Context.Response.ContentType = "application/json; charset=utf-8";
Context.Response.AddHeader("content-length", res_bytes.Length.ToString());
Context.Response.BinaryWrite(res_bytes);
Context.Response.Flush();