Path.Combine很方便,但是.NET框架中是否有类似的URL函数?
我正在寻找这样的语法:
Url.Combine("http://MyUrl.com/", "/Images/Image.jpg")
这将返回:
"http://MyUrl.com/Images/Image.jpg"
Path.Combine很方便,但是.NET框架中是否有类似的URL函数?
我正在寻找这样的语法:
Url.Combine("http://MyUrl.com/", "/Images/Image.jpg")
这将返回:
"http://MyUrl.com/Images/Image.jpg"
当前回答
最近,Combine方法被添加到Energy.Core包中,所以您可能希望使用它来连接URL部分。
string url;
url = Energy.Base.Url.Combine("https://www.youtube.com", "watch?v=NHCgbs3TcYg");
Console.WriteLine(url);
url = Energy.Base.Url.Combine("https://www.youtube.com", "watch?v=NHCgbs3TcYg", "t=150");
Console.WriteLine(url);
此外,它将识别参数部分,因此它将按照您的预期工作(用斜线连接路径,用&符号连接参数)。
https://www.youtube.com/watch?v=NHCgbs3TcYghttps://www.youtube.com/watch?v=NHCgbs3TcYg&t=150
Energy.Base.Url类文档
NuGet图库上的软件包
代码示例
其他回答
组合它们并确保始终正确的一种简单方法是:
string.Format("{0}/{1}", Url1.Trim('/'), Url2);
我有一个无需分配的字符串创建版本,我一直在成功地使用它。
注:
对于第一个字符串:它使用TrimEnd(分隔符)修剪分隔符,因此仅从字符串的末尾开始。对于余数:它使用Trim(分隔符)修剪分隔符-因此路径的起点和终点都是它不附加尾部斜杠/分隔符。虽然可以做一个简单的修改来增加这个能力。
希望你觉得这很有用!
/// <summary>
/// This implements an allocation-free string creation to construct the path.
/// This uses 3.5x LESS memory and is 2x faster than some alternate methods (StringBuilder, interpolation, string.Concat, etc.).
/// </summary>
/// <param name="str"></param>
/// <param name="paths"></param>
/// <returns></returns>
public static string ConcatPath(this string str, params string[] paths)
{
const char separator = '/';
if (str == null) throw new ArgumentNullException(nameof(str));
var list = new List<ReadOnlyMemory<char>>();
var first = str.AsMemory().TrimEnd(separator);
// get length for intial string after it's trimmed
var length = first.Length;
list.Add(first);
foreach (var path in paths)
{
var newPath = path.AsMemory().Trim(separator);
length += newPath.Length + 1;
list.Add(newPath);
}
var newString = string.Create(length, list, (chars, state) =>
{
// NOTE: We don't access the 'list' variable in this delegate since
// it would cause a closure and allocation. Instead we access the state parameter.
// track our position within the string data we are populating
var position = 0;
// copy the first string data to index 0 of the Span<char>
state[0].Span.CopyTo(chars);
// update the position to the new length
position += state[0].Span.Length;
// start at index 1 when slicing
for (var i = 1; i < state.Count; i++)
{
// add a separator in the current position and increment position by 1
chars[position++] = separator;
// copy each path string to a slice at current position
state[i].Span.CopyTo(chars.Slice(position));
// update the position to the new length
position += state[i].Length;
}
});
return newString;
}
基准DotNet输出:
| Method | Mean | Error | StdDev | Median | Ratio | RatioSD | Gen 0 | Allocated |
|---------------------- |---------:|---------:|---------:|---------:|------:|--------:|-------:|----------:|
| ConcatPathWithBuilder | 404.1 ns | 27.35 ns | 78.48 ns | 380.3 ns | 1.00 | 0.00 | 0.3347 | 1,400 B |
| ConcatPath | 187.2 ns | 5.93 ns | 16.44 ns | 183.2 ns | 0.48 | 0.10 | 0.0956 | 400 B |
我使用此代码来解决问题:
string[] brokenBaseUrl = Context.Url.TrimEnd('/').Split('/');
string[] brokenRootFolderPath = RootFolderPath.Split('/');
for (int x = 0; x < brokenRootFolderPath.Length; x++)
{
//if url doesn't already contain member, append it to the end of the string with / in front
if (!brokenBaseUrl.Contains(brokenRootFolderPath[x]))
{
if (x == 0)
{
RootLocationUrl = Context.Url.TrimEnd('/');
}
else
{
RootLocationUrl += String.Format("/{0}", brokenRootFolderPath[x]);
}
}
}
如果您不想在ASP.NET Core(也在Microsoft.Owin中提供)中添加第三方依赖项(如Flurl)或创建自定义扩展方法,则可以使用PathString来构建URI路径。然后,可以使用URI和UriBuilder的组合创建完整的URI。
在这种情况下,应为:
new Uri(new UriBuilder("http", "MyUrl.com").Uri, new PathString("/Images").Add("/Image.jpg").ToString())
这提供了所有组成部分,而无需在基URL中指定分隔符。不幸的是,PathString要求在每个字符串前面加上/,否则它实际上会引发ArgumentException!但至少您可以以易于单元测试的方式确定地构建URI。
//阅读以上所有示例,结果创建了我自己:
static string UrlCombine(params string[] items)
{
if (items?.Any() != true)
{
return string.Empty;
}
return string.Join("/", items.Where(u => !string.IsNullOrWhiteSpace(u)).Select(u => u.Trim('/', '\\')));
}
//用法
UrlCombine("https://microsoft.com","en-us")