在项目中，有时候一些信息不便完全显示，只需要显示部分信息。现在提供一些隐藏敏感信息的操作方法，主要为对信息的截取操作：
1.指定左右字符数量,中间的*的个数和实际长度有关：
代码语言：javascript复制 /// <summary>
/// 隐藏敏感信息
/// </summary>
/// <param name="info">信息实体</param>
/// <param name="left">左边保留的字符数</param>
/// <param name="right">右边保留的字符数</param>
/// <param name="basedOnLeft">当长度异常时，是否显示左边
/// <code>true</code>显示左边，<code>false</code>显示右边
/// </param>
/// <returns></returns>
public static string HideSensitiveInfo(string info, int left, int right, bool basedOnLeft = true)
{
if (string.IsNullOrEmpty(info))
{
throw new ArgumentNullException(info);
}
var sbText = new StringBuilder();
var hiddenCharCount = info.Length - left - right;
if (hiddenCharCount > 0)
{
string prefix = info.Substring(0, left), suffix = info.Substring(info.Length - right);
sbText.Append(prefix);
for (var i = 0; i < hiddenCharCount; i )
{
sbText.Append("*");
}
sbText.Append(suffix);
}
else
{
if (basedOnLeft)
{
if (info.Length > left && left > 0)
{
sbText.Append(info.Substring(0, left) "****");
}
else
{
sbText.Append(info.Substring(0, 1) "****");
}
}
else
{
if (info.Length > right && right > 0)
{
sbText.Append("****" info.Substring(info.Length - right));
}
else
{
sbText.Append("****" info.Substring(info.Length - 1));
}
}
}
return sbText.ToString();
}2.指定左右字符数量,中间的*的个数固定：
代码语言：javascript复制 /// <summary>
/// 隐藏敏感信息
/// </summary>
/// <param name="info">信息实体</param>
/// <param name="left">左边保留的字符数</param>
/// <param name="right">右边保留的字符数</param>
/// <param name="basedOnLeft">当长度异常时，是否显示左边
/// <code>true</code>显示左边，<code>false</code>显示右边
/// <returns></returns>
public static string HideSensitiveInfo1(string info, int left, int right, bool basedOnLeft = true)
{
if (string.IsNullOrEmpty(info))
{
throw new ArgumentNullException(info);
}
var sbText = new StringBuilder();
var hiddenCharCount = info.Length - left - right;
if (hiddenCharCount > 0)
{
string prefix = info.Substring(0, left), suffix = info.Substring(info.Length - right);
sbText.Append(prefix);
sbText.Append("****");
sbText.Append(suffix);
}
else
{
if (basedOnLeft)
{
if (info.Length > left && left > 0)
{
sbText.Append(info.Substring(0, left) "****");
}
else
{
sbText.Append(info.Substring(0, 1) "****");
}
}
else
{
if (info.Length > right && right > 0)
{
sbText.Append("****" info.Substring(info.Length - right));
}
else
{
sbText.Append("****" info.Substring(info.Length - 1));
}
}
}
return sbText.ToString();
}3.“*”数量一定，设置为4个，按信息总长度的比例来取，默认左右各取1/3：
代码语言：javascript复制 /// <summary>
/// 隐藏敏感信息
/// </summary>
/// <param name="info">信息</param>
/// <param name="sublen">信息总长与左子串（或右子串）的比例</param>
/// <param name="basedOnLeft"/>当长度异常时，是否显示左边，默认true，默认显示左边
/// <code>true</code>显示左边，<code>false</code>显示右边
/// <returns></returns>
public static string HideSensitiveInfo(string info, int sublen = 3, bool basedOnLeft = true)
{
if (string.IsNullOrEmpty(info))
{
throw new ArgumentNullException(info);
}
if (sublen <= 1)
{
sublen = 3;
}
var subLength = info.Length / sublen;
if (subLength > 0 && info.Length > (subLength * 2))
{
string prefix = info.Substring(0, subLength), suffix = info.Substring(info.Length - subLength);
return prefix "****" suffix;
}
if (basedOnLeft)
{
var prefix = subLength > 0 ? info.Substring(0, subLength) : info.Substring(0, 1);
return prefix "****";
}
var suffixs = subLength > 0 ? info.Substring(info.Length - subLength) : info.Substring(info.Length - 1);
return "****" suffixs;
}4.隐藏右键详情
代码语言：javascript复制 /// <summary>
/// 隐藏右键详情
/// </summary>
/// <param name="email">邮件地址</param>
/// <param name="left">邮件头保留字符个数，默认值设置为3</param>
/// <returns></returns>
public static string HideEmailDetails(string email, int left = 3)
{
if (string.IsNullOrEmpty(email))
{
throw new ArgumentNullException(email);
}
if (!System.Text.RegularExpressions.Regex.IsMatch(email, @"w ([- .]w )*@w ([-.]w )*.w ([-.]w )*"))
return HideSensitiveInfo(email);
var suffixLen = email.Length - email.LastIndexOf('@');
return HideSensitiveInfo(email, left, suffixLen, false);
}在一些信息的隐藏操作，可以采用js实现，也可以采用jquery插件完成操作，但是在前台进行这样的操作，存在一些风险，在后台完成对字符的信息截取，可以很好的对信息进行保护。
