namespace MyApp.Extensions
{
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using System.Web;
public static class ParseExtensions
{
/// <summary>A string extension method that extracts the hash tags contained in value.</summary>
/// <param name="value">The value to act on.</param>
/// <returns>The extracted hash tags.</returns>
public static List<string> ExtractHashTags(this string value)
{
return Regex.Matches(value, @"#([A-Za-z])([A-Za-z0-9]*)")
.Cast<Match>()
.Select(m => m.Groups[0].Value.Replace("#", string.Empty).Trim())
.Distinct()
.ToList();
}
/// <summary>A string extension method that parses the bold attributes contained in value </summary>
/// <param name="value">The value.</param>
/// <returns>A string.</returns>
public static string ParseBold(this string value)
{
return Regex.Replace(value, @"\*(.*?)\*", AsBoldTag);
}
/// <summary>A string extension method that parses the hashtag attributes contained in value</summary>
/// <param name="value">The value.</param>
/// <returns>A string.</returns>
public static string ParseHashtag(this string value)
{
return Regex.Replace(value, @"#([A-Za-z])([A-Za-z0-9]*)", AsHashtag);
}
/// <summary>A string extension method that parses the italic attributes contained in value</summary>
/// <param name="value">The value.</param>
/// <returns>A string.</returns>
public static string ParseItalic(this string value)
{
return Regex.Replace(value, @"_(.*?)_", AsItalicTag);
}
/// <summary>A string extension method that parses the link attributes contained in value</summary>
/// <param name="value">The value.</param>
/// <returns>A string.</returns>
public static string ParseLink(this string value)
{
return Regex.Replace(value,
@"(\[)([A-Za-z0-9 -_]*)(\])(\()((http|ftp|https):\/\/[\w\-_]+(\.[\w\-_]+)+([\w\-\.,@?^=%&amp;:/~\+#]*[\w\-\@?^=%&amp;/~\+#])?)(\))",
AsUrlTag);
}
/// <summary>Parses the post.</summary>
/// <param name="value">The value.</param>
/// <returns>A string.</returns>
public static string ParsePost(this string value)
{
return value.ParseItalic().ParseBold().ParseHashtag().ParseUsertag().ParseLink();
}
/// <summary>Parses the usertag.</summary>
/// <param name="value">The value.</param>
/// <returns>A string.</returns>
public static string ParseUsertag(this string value)
{
return Regex.Replace(value, @"@([A-Za-z])([A-Za-z0-9]*)", AsUserTag);
}
/// <summary>Expresses the match as a bold tag</summary>
/// <param name="m">The m.</param>
/// <returns>A string.</returns>
private static string AsBoldTag(Match m)
{
var value = m.Value;
var tag = value.Replace("*", string.Empty);
return string.IsNullOrWhiteSpace(tag) ? string.Empty : tag.FormatSpan("bold");
}
/// <summary>Expresses the match as a hashtag</summary>
/// <param name="m">The m.</param>
/// <returns>A string.</returns>
private static string AsHashtag(Match m)
{
var value = m.Value;
var tag = value.Replace("#", string.Empty);
var url = VirtualPathUtility.ToAbsolute($"~/Hashtag/{tag}");
return string.IsNullOrWhiteSpace(tag) ? string.Empty : tag.FormatLink(url, "hashtag-link", "hashtag");
}
/// <summary>Expresses the match as an italic tag</summary>
/// <param name="m">The m.</param>
/// <returns>A string.</returns>
private static string AsItalicTag(Match m)
{
var value = m.Value;
var tag = value.Replace("_", string.Empty);
return string.IsNullOrWhiteSpace(tag) ? string.Empty : tag.FormatSpan("italic");
}
/// <summary>Expresses the match as a URL tag</summary>
/// <param name="m">The m.</param>
/// <returns>A string.</returns>
private static string AsUrlTag(Match m)
{
var desc = m.Groups[2].Value;
var url = m.Groups[5].Value;
return string.IsNullOrWhiteSpace(url) ? string.Empty : desc.FormatLink(url, string.Empty, "link");
}
/// <summary>Expresses the match as a user tag</summary>
/// <param name="m">The m.</param>
/// <returns>A string.</returns>
private static string AsUserTag(Match m)
{
var value = m.Value;
var tag = value.Replace("@", string.Empty);
var url = VirtualPathUtility.ToAbsolute($"~/Profile/{tag}");
return string.IsNullOrWhiteSpace(tag) ? string.Empty : tag.FormatLink(url, "usertag-link", "at");
}
/// <summary>A string extension method that formats the link.</summary>
/// <param name="value">The value.</param>
/// <param name="url">URL of the document.</param>
/// <param name="className">Name of the class.</param>
/// <param name="faIcon"></param>
/// <returns>The formatted link.</returns>
private static string FormatLink(this string value, string url, string className, string faIcon)
{
var cssClass = string.IsNullOrWhiteSpace(className)
? string.Empty
: $" class=\"{className}\"";
return $"<a rel=\"canonical\" href=\"{url}\"{cssClass}><i class=\"fa fa-{faIcon} fa-1x\"></i><span>{value}</span></a>";
}
/// <summary>A string extension method that format span.</summary>
/// <param name="value">The value.</param>
/// <param name="className">Name of the class.</param>
/// <returns>The formatted span.</returns>
private static string FormatSpan(this string value, string className)
{
var cssClass = string.IsNullOrWhiteSpace(className)
? string.Empty
: $" class=\"{className}\"";
return $"<span{cssClass}>{value}</span>";
}
}
}
Comments