public static void AddCssClass(this TagHelperAttributeList attributeList, string cssClass)
{
const string classAttribute = "class";
var existingCssClassValue = attributeList
.FirstOrDefault(x => x.Name == classAttribute)?.Value.ToString();
// If the class attribute doesn't exist, or the class attribute
// value is empty, just add the CSS class to class attribute
if (String.IsNullOrEmpty(existingCssClassValue))
{
attributeList.SetAttribute(classAttribute, cssClass);
}
// Here I use Regular Expression to check if the existing css class
// value has the css class already. If yes, you don't need to add
// that css class again. Otherwise you just add the css class along
// with the existing value.
// \b indicates a word boundary, as you only want to check if
// the css class exists as a whole word.
else if (!Regex.IsMatch(existingCssClassValue, $@"\b{ cssClass }\b", RegexOptions.IgnoreCase))
{
attributeList.SetAttribute(classAttribute, $"{ cssClass } { existingCssClassValue }");
}
}
public static void Merge(this TagHelperAttributeList attributes, string name, object value)
{
var attr = attributes.FirstOrDefault(a => a.Name == name);
if (attr != null)
{
attributes.Remove(attr);
}
attributes.Add(name, $"{value} {attr?.Value}");
}
protected virtual void SetHrefAttribute(string currentPage, TagHelperAttributeList attributeList)
{
var hrefAttribute = attributeList.FirstOrDefault(x => x.Name.Equals("href", StringComparison.OrdinalIgnoreCase));
if (hrefAttribute != null)
{
var pageUrl = TagHelper.Model.PageUrl;
var routeValue = $"currentPage={currentPage}{(TagHelper.Model.Sort.IsNullOrWhiteSpace()? "" : "&sort="+TagHelper.Model.Sort)}";
pageUrl += pageUrl.Contains("?") ? "&" + routeValue : "?" + routeValue;
attributeList.Remove(hrefAttribute);
attributeList.Add(new TagHelperAttribute("href", pageUrl, hrefAttribute.ValueStyle));
}
}
public static void Merge(this TagHelperAttributeList attributes, string name, string value)
{
if (attributes == null)
{
throw new ArgumentNullException(nameof(attributes));
}
var curr = attributes.FirstOrDefault(att => string.Equals(att.Name, name, StringComparison.Ordinal));
if (curr == null)
{
attributes.Add(name, value);
}
else
{
attributes.Remove(curr);
attributes.Add(name, $"{curr.Value} {value}");
}
}
