半角/全角的转换算法

**//// <summary>
/// 转全角的函数(SBC case)
/// </summary>
/// <param name="input">任意字符串</param>
/// <returns>全角字符串</returns>
///<remarks>
///全角空格为12288，半角空格为32
///其他字符半角(33-126)与全角(65281-65374)的对应关系是：均相差65248
///</remarks>
public string ToSBC(string input)
{
//半角转全角：
char[] c=input.ToCharArray();
for (int i = 0; i < c.Length; i++)
{
if (c[i]==32)
{
                     c[i]=(char)12288;
continue;
                 }
if (c[i]<127)
                     c[i]=(char)(c[i]+65248);
             }
return new string(c);               
         }


/**//// <summary>
/// 转半角的函数(DBC case)
/// </summary>
/// <param name="input">任意字符串</param>
/// <returns>半角字符串</returns>
///<remarks>
///全角空格为12288，半角空格为32
///其他字符半角(33-126)与全角(65281-65374)的对应关系是：均相差65248
///</remarks>
public string ToDBC(string input)
{   
char[] c=input.ToCharArray();
for (int i = 0; i < c.Length; i++)
{
if (c[i]==12288)
{
                     c[i]= (char)32;
continue;
                 }
if (c[i]>65280 && c[i]<65375)
                     c[i]=(char)(c[i]-65248);
             }
return new string(c);
         }