ASP.NET获取在线接口数据HttpGet
作者：互联网
哈喽，筒子们。又是令人开心的周六
忙碌（搬砖）的一周又过去了，让我们来看一下今天要写点什么吧
首先接口API相信入行多年的选手都不陌生了，你调用我，我调用你，拿来拿去是很熟悉的都。
那么今天来写点关于调用接口获取Json数据的内容吧【HTTPGET】
首先调用对方地址这个是肯定有的了，那么怎么安全的获取到数据呢。
直接上方法。
private string GetDataJsonBy(string url)
{
string result = string.Empty;
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;
}
HttpWebRequest和HttpWebResponse类是用于发送和接收HTTP数据的最好选择。它们支持一系列有用的属性。这两个类位 于System.Net命名空间，默认情况下这个类对于控制台程序来说是可访问的。请注意，HttpWebRequest对象不是利用new关键字通过构 造函数来创建的，而是利用工厂机制（factory mechanism）通过Create()方法来创建的。另外，你可能预计需要显式地调用一个“Send”方法，实际上不需要。接下来调用 HttpWebRequest.GetResponse()方法返回的是一个HttpWebResponse对象。你可以把HTTP响应的数据流 （stream）绑定到一个StreamReader对象，然后就可以通过ReadToEnd()方法把整个HTTP响应作为一个字符串取回。也可以通过 StreamReader.ReadLine()方法逐行取回HTTP响应的内容。
上面这段说的应该是比较清楚了，那这个Create方法里面具体是怎么做的呢？一起来八一八源代码
// Create - Create a WebRequest.
//
// An overloaded utility version of the real Create that takes a
// string instead of an Uri object.
//
// Input:
// RequestString - Uri string to create.
//
// Returns:
// Newly created WebRequest.
[Obsolete(Obsoletions.WebRequestMessage, DiagnosticId = Obsoletions.WebRequestDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
public static WebRequest Create(string requestUriString)
{
if (requestUriString == null)
{
throw new ArgumentNullException(nameof(requestUriString));
}
return Create(new Uri(requestUriString), false);
}
我们看到了，C#的源码做的还是很好的，在最新版里面这个方法已经是被Obsolete了的。
不过不影响我们看它的实现，看看它内部调用的Create重载是怎么写的
// Create a WebRequest.
//
// This is the main creation routine. We take a Uri object, look
// up the Uri in the prefix match table, and invoke the appropriate
// handler to create the object. We also have a parameter that
// tells us whether or not to use the whole Uri or just the
// scheme portion of it.
//
// Input:
// requestUri - Uri object for request.
// useUriBase - True if we're only to look at the scheme portion of the Uri.
//
// Returns:
// Newly created WebRequest.
private static WebRequest Create(Uri requestUri, bool useUriBase)
{
string LookupUri;
WebRequestPrefixElement? Current = null;
bool Found = false;
if (!useUriBase)
{
LookupUri = requestUri.AbsoluteUri;
}
else
{
// schemes are registered as <schemeName>":", so add the separator
// to the string returned from the Uri object
LookupUri = requestUri.Scheme + ':';
}
int LookupLength = LookupUri.Length;
// Copy the prefix list so that if it is updated it will
// not affect us on this thread.
List<WebRequestPrefixElement> prefixList = PrefixList;
// Look for the longest matching prefix.
// Walk down the list of prefixes. The prefixes are kept longest
// first. When we find a prefix that is shorter or the same size
// as this Uri, we'll do a compare to see if they match. If they
// do we'll break out of the loop and call the creator.
for (int i = 0; i < prefixList.Count; i++)
{
Current = prefixList[i];
// See if this prefix is short enough.
if (LookupLength >= Current.Prefix.Length)
{
// It is. See if these match.
if (string.Compare(Current.Prefix,
0,
LookupUri,
0,
Current.Prefix.Length,
StringComparison.OrdinalIgnoreCase) == 0)
{
// These match. Remember that we found it and break
// out.
Found = true;
break;
}
}
}
if (Found)
{
// We found a match, so just call the creator and return what it does.
WebRequest webRequest = Current!.Creator.Create(requestUri);
return webRequest;
}
// Otherwise no match, throw an exception.
throw new NotSupportedException(SR.net_unknown_prefix);
}
瞧瞧人家这个代码写的，这命名，这质量，这注释。
再瞧瞧我们的项目，诶~（露头会被打死）
源码已贴
后面的代码你们自己扒拉吧，不贴了。【我才不会说我看不懂了】
[HttpGet]
public IHttpActionResult GetPersonnel()
{
DateTime startDay = new DateTime(2019, 5, 1);
DateTime endDay = new DateTime(2019, 5, 2);
TimeSpan leftTime = new DateTime(2020, 12, 1)- startDay;
int leftDay = Convert.ToInt32(leftTime.TotalDays);
#region Info
for (int i = 0; i < leftDay; i++)
{
string uri = "http://main.demo.com/api/personnel/getdemo?beginDate="+startDay.AddDays(i)+"&endDate=" + endDay.AddDays(i);
string resultJson = GetDataJsonBy(uri);
IList<Demo> data = JsonConvert.DeserializeObject<List<Demo>>(resultJson);
foreach (var item in data)
{
Demo entity = Demo.GetList(new { DataId = item.id }.ToJson()).FirstOrDefault();
if (entity == null)
{//save new。
demo.SaveForm("", new nhw_EmployeesEntity{
entityData.Mail = item.mailAddress,
entityData.Photo = item.picture
});
continue;
}
entity.Mail = item.mailAddress;
entity.Photo = item.picture;
demo.SaveForm(entity.ID.ToString(), entity);
}
}
#endregion
return Json("");
}
抛砖引玉，我这里只是贴了一个简单的方法去获取到数据，并且进行了数据库的增改操作。
欢迎大家指正
标签：ASP,string,WebRequest,Create,Uri,prefix,HttpGet,new,NET 来源： https://www.cnblogs.com/SevenWang/p/14014879.html