File Download DownloadTo

JumpKick.HttpLib — File Download DownloadTo

Description

Use .DownloadTo(savePath, ...) to directly download and save network resources to local disk, usually used with Http.Get().
Callback parameters:

1. onProgressChanged：(bytesCopied, totalBytes?)
   • bytesCopied: Number of bytes already downloaded
   • totalBytes: Total file bytes, nullable type (long?)
     If the server does not return the Content‑Length response header, totalBytes.HasValue == false. Download percentage cannot be calculated, only downloaded bytes can be printed.
2. onSuccess：(headers)
   Completion callback for download, you can retrieve response header information.

---

Examples

With progress and completion callback

using System;
using JumpKick.HttpLib;

class Program
{
    static void Main(string[] args)
    {
        string url = "https://codelexample.test/file.zip";
        string savePath = @"E:\httplib.zip";

        Http.Get(url)
        .DownloadTo(
            savePath,
            onProgressChanged: (bytesCopied, totalBytes) =>
            {
                if (totalBytes.HasValue)
                {
                    // *1.0d force floating‑point arithmetic to avoid integer division yielding zero
                    double progress = (bytesCopied / totalBytes.Value * 1.0d) * 100;
                    Console.WriteLine($"Download progress：{progress:F2} %");
                }
                Console.WriteLine($"Downloaded bytes：{bytesCopied} bytes");
            },
            onSuccess: (headers) =>
            {
                Console.WriteLine("\nFile download completed");
            }
        )
        .OnFail(ex =>
        {
            Console.WriteLine("Download error：" + ex.Message);
        })
        .Go();

        Console.ReadKey();
    }
}Code language: JavaScript (javascript)

Example‑Minimal Download

No progress monitoring

using System;
using JumpKick.HttpLib;

class Program
{
    static void Main(string[] args)
    {
        Http.Get("https://httpbin.org/image/png")
        .DownloadTo(@"E:\test.png",
            onSuccess: headers =>
            {
                Console.WriteLine("Download finished");
            })
        .OnFail(ex => Console.WriteLine(ex.Message))
        .Go();

        Console.ReadKey();
    }
}Code language: JavaScript (javascript)

Exception Test

Supply non‑existent resource address to catch 404 error

using System;
using JumpKick.HttpLib;

class Program
{
    static void Main(string[] args)
    {
        // Invalid link triggers 404
        Http.Get("https://httpbin.org/notfoundfile")
        .DownloadTo(@"E:\error.png",
            onProgressChanged: (bytesCopied, totalBytes) =>
            {
                Console.WriteLine($"Downloaded：{bytesCopied} bytes");
            },
            onSuccess: headers =>
            {
                Console.WriteLine("Download finished");
            })
        .OnFail(ex =>
        {
            Console.WriteLine("Caught exception：" + ex.Message);
        })
        .Go();

        Console.ReadKey();
    }
}Code language: JavaScript (javascript)

Summary

Feature	API	Core Method
GET Request	Http.Get(url)	Basic query, file download .DownloadTo()
POST Form	Http.Post(url)	.Form() form key‑value pairs
POST JSON	Http.Post(url)	.Body(string, mediaType)
File Upload	Http.Post(url)	.Upload() + NamedFileStream

File Download DownloadTo