C# HTTP 请求库封装
/// <summary>
/// http协议访问方法封装
/// </summary>
public class NetHelper
{
/// <summary>
/// 指定Url地址使用Get 方式获取全部字符串
/// </summary>
/// <param name="url">请求链接地址</param>
/// <returns></returns>
public static string Get(string url)
{
string result = "";
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream stream = resp.GetResponseStream();
try
{
//获取内容
using (StreamReader reader = new StreamReader(stream))
{
result = reader.ReadToEnd();
}
}
finally
{
stream.Close();
}
return result;
}
/// <summary>
/// 发送Get请求
/// </summary>
/// <param name="url">地址</param>
/// <param name="dic">请求参数定义</param>
/// <returns></returns>
public static string Get(string url, Dictionary<string, string> dic)
{
string result = "";
StringBuilder builder = new StringBuilder();
builder.Append(url);
if (dic.Count > 0)
{
builder.Append("?");
int i = 0;
foreach (var item in dic)
{
if (i > 0)
builder.Append("&");
builder.AppendFormat("{0}={1}", item.Key, item.Value);
i++;
}
}
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(builder.ToString());
//添加参数
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream stream = resp.GetResponseStream();
try
{
//获取内容
using (StreamReader reader = new StreamReader(stream))
{
result = reader.ReadToEnd();
}
}
finally
{
stream.Close();
}
return result;
}
#region Post提交
/// <summary>
/// 指定Post地址使用Get 方式获取全部字符串
/// </summary>
/// <param name="url">请求后台地址</param>
/// <returns></returns>
public static string Post(string url)
{
string result = "";
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
req.Method = "POST";
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream stream = resp.GetResponseStream();
//获取内容
using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
{
result = reader.ReadToEnd();
}
return result;
}
/// <summary>
/// 指定Post地址使用Get 方式获取全部字符串
/// </summary>
/// <param name="url">请求后台地址</param>
/// <param name="content">Post提交数据内容(utf-8编码的)</param>
/// <returns></returns>
public static string Post(string url, string content)
{
string result = "";
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
#region 添加Post 参数
byte[] data = Encoding.UTF8.GetBytes(content);
req.ContentLength = data.Length;
using (Stream reqStream = req.GetRequestStream())
{
reqStream.Write(data, 0, data.Length);
reqStream.Close();
}
#endregion
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream stream = resp.GetResponseStream();
//获取响应内容
using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
{
result = reader.ReadToEnd();
}
return result;
}
/// <summary>
/// 指定Post地址使用Get 方式获取全部字符串
/// </summary>
/// <param name="url">请求后台地址</param>
/// <returns></returns>
public static string Post(string url, Dictionary<string, string> dic)
{
string result = "";
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
#region 添加Post 参数
StringBuilder builder = new StringBuilder();
int i = 0;
foreach (var item in dic)
{
if (i > 0)
builder.Append("&");
builder.AppendFormat("{0}={1}", item.Key, item.Value);
i++;
}
byte[] data = Encoding.UTF8.GetBytes(builder.ToString());
req.ContentLength = data.Length;
using (Stream reqStream = req.GetRequestStream())
{
reqStream.Write(data, 0, data.Length);
reqStream.Close();
}
#endregion
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream stream = resp.GetResponseStream();
//获取响应内容
using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
{
result = reader.ReadToEnd();
}
return result;
}
#endregion
#region 简单下载文件
/// <summary>
/// 下载外网文件到指定位置
/// </summary>
/// <param name="url">下载的地址</param>
/// <param name="target">保存的地址</param>
/// <returns></returns>
public static bool DownLoad(string url, string target)
{
try
{
WebClient client = new WebClient();
client.DownloadFile(url, target);
return true;
}
catch (Exception ex)
{
// ex.Message += "下载外网文件失败," + ex.Message;
throw new Exception("下载外网文件失败," + ex.Message);
}
}
/// <summary>
/// 异步下载外网文件到指定位置
/// </summary>
/// <param name="url">下载的地址</param>
/// <param name="target">保存的地址</param>
/// <returns></returns>
public static bool DownLoadAsnc(string url, string target)
{
try
{
WebClient client = new WebClient();
//使用异步下载
client.DownloadFileAsync(new Uri(url), target);
return true;
}
catch
{
return false;
}
}
/// <summary>
/// 下载文件，返回下载任务
/// </summary>
/// <param name="url">下载地址</param>
/// <param name="target">保存地址</param>
/// <returns></returns>
public static Task DownLoadTaskAsnc(string url, string target)
{
WebClient client = new WebClient();
//使用异步下载
return client.DownloadFileTaskAsync(new Uri(url), target);
}
/// <summary>
/// 下载第三方用户的头像,并保存到当前用户的文件夹
/// ----目前没有用到
/// </summary>
/// <param name="url"></param>
/// <param name="userid"></param>
/// <returns></returns>
public static string DownLoadTouX(string url, int userid)
{
// string userpath = HttpContext.Current.Server.MapPath("~/content/AboveUploadFiles/" + userid);
string userpath = @"H:\Content\AboveUploadFiles\" + userid;
string username = Guid.NewGuid().ToString() + ".png";
string result = userid + "\\" + username;
//判断文件夹是否存在
if (Directory.Exists(userpath) == false)
{
Directory.CreateDirectory(userpath);
}
//文件全名
userpath = userpath + "\\" + username;
//下载图片，并格式准换
try
{
WebClient client = new WebClient();
Stream stream = client.OpenRead(url);
Bitmap bit = new Bitmap(stream);
//图片格式转换
//Graphics g = Graphics.FromImage(bit);
//g.InterpolationMode = InterpolationMode.HighQualityBicubic;
//g.SmoothingMode = SmoothingMode.HighQuality;
//g.CompositingQuality = CompositingQuality.HighQuality;
//Bitmap png = new Bitmap(bit, bit.Width, bit.Height);
//g.DrawImage(png, 0, 0);
//png.Save(userpath, Drawing.Imaging.ImageFormat.Png);
//g.Dispose();
//png.Dispose();
bit.Save(userpath, System.Drawing.Imaging.ImageFormat.Png);
stream.Close();
client.Dispose();
return result;
}
catch (Exception ex)
{
return "";
}
}
#endregion
