cscの作法 その24 WebRequest

概要

cscの作法、調べてみた。
練習問題やってみた。

練習問題

pdfダウンローダーを作れ。

サンプルコード

using System;
using System.Windows.Forms;
using System.Drawing;
using System.IO;
using System.Net;
using System.Text;

class form1: Form {
	TextBox bo1;
	form1() {
		Text = "download";
		ClientSize = new Size(580, 200);
		bo1 = new TextBox();
		bo1.Location = new Point(50, 50);
		bo1.Width = 500;
		bo1.Text = "https://www.jitec.ipa.go.jp/1_04hanni_sukiru/mondai_kaitou_2015h27_1/2015h27h_fe_am_qs.pdf";
		Controls.AddRange(new Control[] {
			bo1
		});
		Button btn1 = new Button();
		btn1.Location = new Point(50, 90);
		btn1.Text = "test";
		btn1.Click += btn1_Click;
		Controls.AddRange(new Control[] {
			btn1
		});
	}
	void btn1_Click(object sender, System.EventArgs e) {
		string url = bo1.Text;
		string filename = DateTime.Now.ToString("HH-mm-ss") + ".pdf";
		WebRequest req = WebRequest.Create(url);
		WebResponse res = req.GetResponse();
		Stream st = res.GetResponseStream();
		byte[] buf = new byte[32768];
		MemoryStream ms = new MemoryStream();
		while (true)
		{
			int read = st.Read(buf, 0, buf.Length);
			if (read > 0)
			{
				ms.Write(buf, 0, read);
			}
			else
			{
				break;
			}
		}
		FileStream fs = new FileStream(filename, FileMode.Create);
		byte[] wbuf = new byte[ms.Length];
		ms.Seek(0, SeekOrigin.Begin);
		ms.Read(wbuf, 0, wbuf.Length);
		fs.Write(wbuf, 0, wbuf.Length);
		fs.Close();
		MessageBox.Show(filename);
	}
	[STAThread]
	public static void Main() {
		Application.Run(new form1());
	}
}

以上。