1.c#断点续传下载文件
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Net;
using System.Text.RegularExpressions;
using System.Runtime.InteropServices;
namespace DownLoadFile
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
string strName = "";//记录要下载的文件名
private void Form1_Load(object sender, EventArgs e)
{
try
{
//监视剪贴板是否有数据
string strPath = Clipboard.GetData(DataFormats.Text).ToString();
//验证网址格式
if (Regex.IsMatch(strPath, @"http(s)?://([\w-]+\.)+[\w-]+(/[\w- ./?%&=]*)?"))
{
textBox1.Text = strPath;
strName = strPath.Substring(strPath.LastIndexOf("/") + 1);
}
//读取文件存放的默认路径
textBox2.Text = ReadString("SysSet", "RootPath", "", Application.StartupPath + "\\SysSet.ini");
textBox3.Text = strName;
}
catch { }
}
//下载文件
private void button1_Click(object sender, EventArgs e)
{
if (textBox2.Text.EndsWith("\\"))
DownloadFile(textBox2.Text + strName, textBox1.Text);
else
DownloadFile(textBox2.Text + "\\" + strName, textBox1.Text);
}
//选择存放路径,并存储到INI文件中
private void button4_Click(object sender, EventArgs e)
{
folderBrowserDialog1.SelectedPath = ReadString("SysSet", "RootPath", "", Application.StartupPath + "\\SysSet.ini");
if (folderBrowserDialog1.ShowDialog() == DialogResult.OK)
{
textBox2.Text = folderBrowserDialog1.SelectedPath;
WritePrivateProfileString("SysSet", "RootPath", folderBrowserDialog1.SelectedPath, Application.StartupPath + "\\SysSet.ini");
}
}
//下载地址改变时,相应的下载文件发生改变
private void textBox1_TextChanged(object sender, EventArgs e)
{
if (textBox1.Text.Contains("/"))
{
textBox3.Text = textBox1.Text.Substring(textBox1.Text.LastIndexOf("/") + 1);
strName = textBox3.Text;
}
}
#region 以断点续传方式下载文件
/// <summary>
/// 以断点续传方式下载文件
/// </summary>
/// <param name="strFileName">下载文件的保存路径</param>
/// <param name="strUrl">文件下载地址</param>
public void DownloadFile(string strFileName, string strUrl)
{
//打开上次下载的文件或新建文件
long SPosition = 0;
FileStream FStream;
if (File.Exists(strFileName))
{
FStream = File.OpenWrite(strFileName);
SPosition = FStream.Length;
FStream.Seek(SPosition, SeekOrigin.Current);//移动文件流中的当前指针
}
else
{
FStream = new FileStream(strFileName, FileMode.Create);
SPosition = 0;
}
//打开网络连接
try
{
HttpWebRequest myRequest = (HttpWebRequest)HttpWebRequest.Create(strUrl);
if (SPosition > 0)
myRequest.AddRange((int)SPosition);//设置Range值
//向服务器请求,获得服务器的回应数据流
Stream myStream = myRequest.GetResponse().GetResponseStream();
byte[] btContent = new byte[512];
int intSize = 0;
intSize = myStream.Read(btContent, 0, 512);
while (intSize > 0)
{
FStream.Write(btContent, 0, intSize);
intSize = myStream.Read(btContent, 0, 512);
}
FStream.Close();
myStream.Close();
MessageBox.Show("文件下载完成!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
catch
{
FStream.Close();
}
}
#endregion
#region 为INI文件中指定的节点取得字符串
/// <summary>
/// 为INI文件中指定的节点取得字符串
/// </summary>
/// <param name="lpAppName">欲在其中查找关键字的节点名称</param>
/// <param name="lpKeyName">欲获取的项名</param>
/// <param name="lpDefault">指定的项没有找到时返回的默认值</param>
/// <param name="lpReturnedString">指定一个字串缓冲区,长度至少为nSize</param>
/// <param name="nSize">指定装载到lpReturnedString缓冲区的最大字符数量</param>
/// <param name="lpFileName">INI文件名</param>
/// <returns>复制到lpReturnedString缓冲区的字节数量,其中不包括那些NULL中止字符</returns>
[DllImport("kernel32")]
public static extern int GetPrivateProfileString(
string lpAppName,
string lpKeyName,
string lpDefault,
StringBuilder lpReturnedString,
int nSize,
string lpFileName);
#endregion
#region 修改INI文件中内容
/// <summary>
/// 修改INI文件中内容
/// </summary>
/// <param name="lpApplicationName">欲在其中写入的节点名称</param>
/// <param name="lpKeyName">欲设置的项名</param>
/// <param name="lpString">要写入的新字符串</param>
/// <param name="lpFileName">INI文件名</param>
/// <returns>非零表示成功,零表示失败</returns>
[DllImport("kernel32")]
public static extern int WritePrivateProfileString(
string lpApplicationName,
string lpKeyName,
string lpString,
string lpFileName);
#endregion
#region 从INI文件中读取指定节点的内容
/// <summary>
/// 从INI文件中读取指定节点的内容
/// </summary>
/// <param name="section">INI节点</param>
/// <param name="key">节点下的项</param>
/// <param name="def">没有找到内容时返回的默认值</param>
/// <param name="def">要读取的INI文件</param>
/// <returns>读取的节点内容</returns>
public static string ReadString(string section, string key, string def, string fileName)
{
StringBuilder temp = new StringBuilder(1024);
GetPrivateProfileString(section, key, def, temp, 1024, fileName);
return temp.ToString();
}
#endregion
private void button3_Click(object sender, EventArgs e)
{
this.Close();
}
}
}
2.显示效果