I need to write the following data into a text file using JSON format in C#. The brackets are important for it to be valid JSON format.
[
{
"Id": 1,
"SSN": 123,
"Message": "whatever"
},
{
"Id": 2,
"SSN": 125,
"Message": "whatever"
}
]
Here is my model class:
public class data
{
public int Id { get; set; }
public int SSN { get; set; }
public string Message { get; set;}
}
Update 2020: It's been 7 years since I wrote this answer. It still seems to be getting a lot of attention. In 2013 Newtonsoft Json.Net was THE answer to this problem. Now it's still a good answer to this problem but it's no longer the the only viable option . To add some up-to-date caveats to this answer:
System.Text.Json
serialiser (see below) JavaScriptSerializer
have thankfully passed and this class isn't even in .Net Core. This invalidates a lot of the comparisons ran by Newtonsoft.System.Text.Json
serializer has over Newtonsoft is it's support for async
/ await
Are Json.Net's days numbered? It's still used a LOT and it's still used by MS libraries. So probably not. But this does feel like the beginning of the end for this library that may well of just run it's course.
A new kid on the block since writing this is System.Text.Json
which has been added to .Net Core 3.0. Microsoft makes several claims to how this is, now, better than Newtonsoft . Including that it is faster than Newtonsoft . I'd advise you to test this yourself.
Examples:
using System.Text.Json;
using System.Text.Json.Serialization;
List<data> _data = new List<data>();
_data.Add(new data()
{
Id = 1,
SSN = 2,
Message = "A Message"
});
string json = JsonSerializer.Serialize(_data);
File.WriteAllText(@"D:\path.json", json);
or
using System.Text.Json;
using System.Text.Json.Serialization;
List<data> _data = new List<data>();
_data.Add(new data()
{
Id = 1,
SSN = 2,
Message = "A Message"
});
using FileStream createStream = File.Create(@"D:\path.json");
await JsonSerializer.SerializeAsync(createStream, _data);
Another option is Json.Net , see example below:
List<data> _data = new List<data>();
_data.Add(new data()
{
Id = 1,
SSN = 2,
Message = "A Message"
});
string json = JsonConvert.SerializeObject(_data.ToArray());
//write string to file
System.IO.File.WriteAllText(@"D:\path.txt", json);
Or the slightly more efficient version of the above code (doesn't use a string as a buffer):
//open file stream
using (StreamWriter file = File.CreateText(@"D:\path.txt"))
{
JsonSerializer serializer = new JsonSerializer();
//serialize object directly into file stream
serializer.Serialize(file, _data);
}
Documentation: Serialize JSON to a file
The example in Liam's answer saves the file as string in a single line. I prefer to add formatting. Someone in the future may want to change some value manually in the file. If you add formatting it's easier to do so.
The following adds basic JSON indentation:
string json = JsonConvert.SerializeObject(_data.ToArray(), Formatting.Indented);
有使用JavaScriptSerializer Class 的内置功能:
var json = JavaScriptSerializer.Serialize(data);
var responseData = //Fetch Data
string jsonData = JsonConvert.SerializeObject(responseData, Formatting.None);
System.IO.File.WriteAllText(Server.MapPath("~/JsonData/jsondata.txt"), jsonData);
If you like the StreamWriter option, you can also use formatting:
using (StreamWriter file = File.CreateText(mFileName))
{
JsonSerializer serializer = new JsonSerializer();
serializer.Formatting = Formatting.Indented;
serializer.Serialize(file, Current);
}
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.