WebHeaderCollection.Get 方法

定义

命名空间:

System.Net

程序集:

System.Net.WebHeaderCollection.dll

从集合中获取标头的值。

重载

Get(Int32)	获取集合中特定标头的值，该值由索引指定到集合中。
Get(String)	获取集合中特定标头的值，该值由标头名指定。

Get(Int32)

Source:

WebHeaderCollection.cs

获取集合中特定标头的值，该值由索引指定到集合中。

public:
 override System::String ^ Get(int index);

public override string? Get (int index);

override this.Get : int -> string

Public Overrides Function Get (index As Integer) As String

参数

index

Int32

要从集合中获取的从零开始的键索引。

返回

String

一个 String，它包含指定标头的值。

例外

ArgumentOutOfRangeException

index 为负数。

- 或 -

index 超出了集合的大小。

示例

下面的代码示例使用 Get 方法检索 中的 WebHeaderCollection标头值。

if (args.Length == 0)
{
    Console.WriteLine("must specify a URL!");
    return;
}
string server = args[0];

// Create the web request 
HttpWebRequest myHttpWebRequest = 
    (HttpWebRequest) WebRequest.Create(server);
myHttpWebRequest.Timeout = 1000;
// Get the associated response for the above request.
HttpWebResponse myHttpWebResponse = 
    (HttpWebResponse) myHttpWebRequest.GetResponse();

// Get the headers associated with the response.
WebHeaderCollection myWebHeaderCollection = 
    myHttpWebResponse.Headers;

for(int i = 0; i < myWebHeaderCollection.Count; i++)
{
    String header = myWebHeaderCollection.GetKey(i);
    String[] values = 
        myWebHeaderCollection.GetValues(header);
    if(values.Length > 0) 
    {
        Console.WriteLine("The values of {0} header are : "
                         , header);
        for(int j = 0; j < values.Length; j++) 
            Console.WriteLine("\t{0}", values[j]);
    }
    else
        Console.WriteLine("There is no value associated" +
            "with the header");
}
Console.WriteLine("");

// Get the headers again, using new properties (Keys, 
// AllKeys, Clear) and methods (Get and GetKey)

string[] headers = myWebHeaderCollection.AllKeys;

// enumerate through the header collection.
foreach (string s in headers)
{
    Console.WriteLine("Header {0}, value {1}",
        s,
        myWebHeaderCollection.Get(s) );
}

Console.WriteLine("");

// show the use of Get(Int32) and GetValue(Int32)
if (myWebHeaderCollection.Count > 0)
{
    // get the name and value of the first header
    int index=0;
    Console.WriteLine("Header {0}: name {1}, value {2}",
        index, 
        myWebHeaderCollection.GetKey(index),
        myWebHeaderCollection.Get(index));
}

myWebHeaderCollection.Clear();

myHttpWebResponse.Close();

Get(String)

Source:

WebHeaderCollection.cs

获取集合中特定标头的值，该值由标头名指定。

public:
 override System::String ^ Get(System::String ^ name);

public override string? Get (string? name);

override this.Get : string -> string

Public Overrides Function Get (name As String) As String

参数

name

String

Web 标头的名称。

返回

String

一个 String，它保存指定标头的值。

示例

下面的代码示例使用 Get 属性检索 中的 WebHeaderCollection标头值。

if (args.Length == 0)
{
    Console.WriteLine("must specify a URL!");
    return;
}
string server = args[0];

// Create the web request 
HttpWebRequest myHttpWebRequest = 
    (HttpWebRequest) WebRequest.Create(server);
myHttpWebRequest.Timeout = 1000;
// Get the associated response for the above request.
HttpWebResponse myHttpWebResponse = 
    (HttpWebResponse) myHttpWebRequest.GetResponse();

// Get the headers associated with the response.
WebHeaderCollection myWebHeaderCollection = 
    myHttpWebResponse.Headers;

for(int i = 0; i < myWebHeaderCollection.Count; i++)
{
    String header = myWebHeaderCollection.GetKey(i);
    String[] values = 
        myWebHeaderCollection.GetValues(header);
    if(values.Length > 0) 
    {
        Console.WriteLine("The values of {0} header are : "
                         , header);
        for(int j = 0; j < values.Length; j++) 
            Console.WriteLine("\t{0}", values[j]);
    }
    else
        Console.WriteLine("There is no value associated" +
            "with the header");
}
Console.WriteLine("");

// Get the headers again, using new properties (Keys, 
// AllKeys, Clear) and methods (Get and GetKey)

string[] headers = myWebHeaderCollection.AllKeys;

// enumerate through the header collection.
foreach (string s in headers)
{
    Console.WriteLine("Header {0}, value {1}",
        s,
        myWebHeaderCollection.Get(s) );
}

Console.WriteLine("");

// show the use of Get(Int32) and GetValue(Int32)
if (myWebHeaderCollection.Count > 0)
{
    // get the name and value of the first header
    int index=0;
    Console.WriteLine("Header {0}: name {1}, value {2}",
        index, 
        myWebHeaderCollection.GetKey(index),
        myWebHeaderCollection.Get(index));
}

myWebHeaderCollection.Clear();

myHttpWebResponse.Close();

注解

如果集合中没有name标头，则此方法返回 null 。