/// <summary>
/// 用于StringHelper类从字符串中挑选符合条件的数字、字母、中文、全角字符, 选项可以叠加使用，如 StringFilterOptions.HoldLetter|StringFilterOptions.HoldNumber 表示从字符串中选取字母和数字
/// </summary>
/// <param name="str"></param>
/// <param name="options"></param>
/// <returns></returns>
public static string FilterInvalidChar(string str, StringFilterOptions options)
{
if (string.IsNullOrEmpty(str))
{
return(string.Empty);
}
StringBuilder builder = new StringBuilder(str.Length);
for (int i = 0; i < str.Length; i++)
{
int num2 = str[i];
if (((num2 >= 0x30) && (num2 <= 0x39)) && ((StringFilterOptions.HoldNumber & options) == StringFilterOptions.HoldNumber))
{
builder.Append(str[i]);
}
else if ((((num2 >= 0x41) && (num2 <= 90)) || ((num2 >= 0x61) && (num2 <= 0x7a))) && ((StringFilterOptions.HoldLetter & options) == StringFilterOptions.HoldLetter))
{
builder.Append(str[i]);
}
else if (((num2 >= 0x4e00) && (num2 <= 0x9fa5)) && ((StringFilterOptions.HoldChinese & options) == StringFilterOptions.HoldChinese))
{
builder.Append(str[i]);
}
else if (((((num2 >= 0xff10) && (num2 <= 0xff19)) || ((num2 >= 0xff21) && (num2 <= 0xff3a))) || ((num2 >= 0xff41) && (num2 <= 0xff5a))) && ((StringFilterOptions.SBCToDBC & options) == StringFilterOptions.SBCToDBC))
{
builder.Append((char)(num2 - 0xfee0));
}
}
return(builder.ToString());
}
/// <summary>
/// 得到输入字符串哈希值的长度
/// </summary>
/// <param name="input"></param>
/// <param name="options"></param>
/// <returns></returns>
public static decimal GetHashKey(string input, StringFilterOptions options)
{
ulong num;
if (string.IsNullOrEmpty(input))
{
return(0M);
}
input = FilterInvalidChar(input, options);
var data = Encoding.UTF8.GetBytes(input);
var encryData = Md5.Encrypt(data);
num = BitConverter.ToUInt64(encryData, 4);
return(DataConverter.CDecimal(num));
}
private static object AlterParameters(StringFilterOptions operation, object parameters)
{
if (operation == StringFilterOptions.StripTags)
{
// Convert the given tags to the format expected by strip_tags
PhpArray tags = (parameters as PhpArray);
if (tags != null)
{
StringBuilder sb = new StringBuilder();
foreach (object o in tags)
{
sb.Append('<');
sb.Append(Core.Convert.ObjectToString(o));
sb.Append('>');
}
return sb.ToString();
}
else
{
// The allowable_tags is expected to be a string
return Core.Convert.ObjectToString(parameters);
}
}
return parameters;
}
/// <summary>Creates a new instance of this filter with additional parameters.</summary>
public StringFilter(StringFilterOptions operation, object parameters)
: base(AlterParameters(operation, parameters))
{
this.operation = operation;
}
