从代码中更改CSS类

我采用了AnthonyWJones的原始代码并对其进行了修改,使其在任何情况下都能正常工作:

static class WebControlsExtensions
    {
        public static void AddCssClass(this WebControl control, string cssClass)
        {
            List<string> classes = control.CssClass.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).ToList();

            classes.Add(cssClass);

            control.CssClass = classes.ToDelimitedString(" ");
        }

        public static void RemoveCssClass(this WebControl control, string cssClass)
        {
            List<string> classes = control.CssClass.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).ToList();

            classes.Remove(cssClass);

            control.CssClass = classes.ToDelimitedString(" ");
        }
    }

    static class StringExtensions
    {
        public static string ToDelimitedString(this IEnumerable<string> list, string delimiter)
        {
            StringBuilder sb = new StringBuilder();
            foreach (string item in list)
            {
                if (sb.Length > 0)
                    sb.Append(delimiter);

                sb.Append(item);
            }

            return sb.ToString();
        }
    }

在C#3中,你可以添加一些扩展方法。

 static class WebControlsExtensions
 {
     public static void AddCssClass (this WebControl control, string cssClass)
     {
         control.CssClass += " " + cssClass;
     }
     public static void RemoveCssClass (this WebControl control, string cssClass)
     {
         control.CssClass = control.CssClass.replace(" " + cssClass, "");
     }
 }

用途:-

ctl.AddCssClass("ReadOnly");
ctl.RemoveCssClass("ReadOnly");

请注意,RemoveCssClass旨在仅删除由AddCssClass添加的类,并且有一个限制,即添加2个额外类名时,最短名称不应与最长名称的开头完全匹配。例如,如果您添加了“test”和“test2”,则无法在不损坏CssClass的情况下删除测试。通过RegEx可以改进这一点,我希望上述内容足以满足您的需求。

注意,如果你没有C#3,那么删除 this 从第一个参数中提取关键字,并以传统方式使用静态方法。

相关。..如果你只是想根据条件切换一个类。..

bool disable = true;      // this will vary (true/false) based on UI state

string newClass = disable ? "BtnGray" : "BtnPink";

string currentClass = disable ? "BtnPink" : "BtnGray";

myButton.CssClass = myButton.CssClass.Replace( currentClass, newClass );

此版本在添加给定类之前会进行检查,以确保尚未添加该类。

public static void CssAddClass(this WebControl control, string className)
{
    var classNames = control.CssClass.Split
        (new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);

    if (classNames.Contains(className))
    {
        return;
    }

    control.CssClass = string.Concat
        (classNames.Select(name => name + " ").ToArray()) + className;
}

public static void CssRemoveClass(this WebControl control, string className)
{
    var classNames = from name in control.CssClass.
                         Split(new[] {' '}, StringSplitOptions.RemoveEmptyEntries)
                     where name != className
                     select name + " ";


    control.CssClass = string.Concat(classNames.ToArray()).TrimEnd();
}

我为C#3之前的版本做了一个版本:

        public static class WebControlsExtensions
        {
            public static void AddCssClass(WebControl control, string cssClass)
            {
                string[] cssClasses = control.CssClass.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
                List<string> classes = new List<string>(cssClasses);

                if (!classes.Contains(cssClass)) {
                    classes.Add(cssClass);
                }

                control.CssClass = StringExtensions.ToDelimitedString(classes, " ");
            }

            public static void RemoveCssClass(WebControl control, string cssClass)
            {
                string[] cssClasses = control.CssClass.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
                List<string> classes = new List<string>(cssClasses);

                bool removed = true;
                while (removed) {
                    removed = classes.Remove(cssClass);
                }

                control.CssClass = StringExtensions.ToDelimitedString(classes, " ");
            }
    }
    static class StringExtensions {
        public static string ToDelimitedString(List<string> list, string delimiter)
        {
            StringBuilder sb = new StringBuilder();
            foreach (string item in list) {
                if (sb.Length > 0)
                    sb.Append(delimiter);

                sb.Append(item);
            }

            return sb.ToString();
        }
    }

使用方式如下:

WebControlsExtensions.AddCssClass(ctl, "classname");
WebControlsExtensions.RemoveCssClass(ctl, "classname");

这个只会添加一个尚未存在的类。它还将删除一个类的所有实例(如果由于某种原因,其中有多个实例)

纯净。NET 2.0(没有扩展!没有LINQ!没有RegEx!没有不必要的WebControl类!)。 这些方法非常通用,不仅适用于CSS类。

public static string AddCssClass(string classContainer, string className)
    {
        if (string.IsNullOrEmpty(classContainer)) return className ?? string.Empty;
        if (string.IsNullOrEmpty(className)) return classContainer;

        var classNames = classContainer.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
        if (Array.Exists(classNames, delegate(string s) { return s.Equals(className); })) return classContainer;

        return classContainer + " " + className;
    }

    public static string RemoveCssClass(string classContainer, string className)
    {
        if (string.IsNullOrEmpty(classContainer)) return className ?? string.Empty;
        if (string.IsNullOrEmpty(className)) return classContainer;

        var classNames = classContainer.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
        int index = Array.FindIndex(classNames, delegate(string s) { return s.Equals(className); });
        if (index >= 0)
        {
            return string.Join(" ", classNames, 0, index) +
                (   index + 1 < classNames.Length ?
                    " " + string.Join(" ", classNames, index + 1, classNames.Length - index - 1)
                    :
                    string.Empty    );
        }

        return classContainer;
    }

    public static string ToggleCssClass(string classContainer, string className)
    {
        if (string.IsNullOrEmpty(classContainer)) return className ?? string.Empty;
        if (string.IsNullOrEmpty(className)) return classContainer;

        var classNames = classContainer.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);

        if (Array.Exists(classNames, delegate(string s) { return s.Equals(className); })) return RemoveCssClass(classContainer, className);

        return classContainer + " " + className;
    }

你能自己定制课程吗?源自ASP。NET按钮,并为只读添加一个属性。某处。..可能在OnPreRender中,您可以检查新属性并相应地设置(或不设置)CSSClass属性。