我現在就遇到這樣的問題，查詢的東東放在頁面，而且那個頁面我根本不想讓他是.aspx結尾的，哈，感覺HTML的挺不錯，而且里面的控件也是用HTML對象的。

下面先來看兩個函數，UTF16轉UTF8和UTF8轉Utf16的。
function utf16to8(str) {
??? var out, i, len, c;

??? out = "";
??? len = str.length;
??? for(i = 0; i < len; i++) {
?c = str.charCodeAt(i);
?if ((c >= 0x0001) && (c <= 0x007F)) {
???? out += str.charAt(i);
?} else if (c > 0x07FF) {
???? out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
???? out += String.fromCharCode(0x80 | ((c >>? 6) & 0x3F));
???? out += String.fromCharCode(0x80 | ((c >>? 0) & 0x3F));
?} else {
???? out += String.fromCharCode(0xC0 | ((c >>? 6) & 0x1F));
???? out += String.fromCharCode(0x80 | ((c >>? 0) & 0x3F));
?}
??? }
??? return out;
}

function utf8to16(str) {
??? var out, i, len, c;
??? var char2, char3;

??? out = "";
??? len = str.length;
??? i = 0;
??? while(i < len) {
?c = str.charCodeAt(i++);
?switch(c >> 4)
?{
?? case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
???? // 0xxxxxxx
???? out += str.charAt(i-1);
???? break;
?? case 12: case 13:
???? // 110x xxxx?? 10xx xxxx
???? char2 = str.charCodeAt(i++);
???? out += String.fromCharCode(((c & 0x1F) << 6) | (char2 & 0x3F));
???? break;
?? case 14:
???? // 1110 xxxx? 10xx xxxx? 10xx xxxx
???? char2 = str.charCodeAt(i++);
???? char3 = str.charCodeAt(i++);
???? out += String.fromCharCode(((c & 0x0F) << 12) |
??????? ((char2 & 0x3F) << 6) |
??????? ((char3 & 0x3F) << 0));
???? break;
?}
??? }

??? return out;
}

那么為什么需要進行轉化呢？因為在JavaScript中獲得的中文字符是用UTF16進行編碼的，和我們統一的頁面標準格式UTF-8可不一樣哦，所以需要先進行轉化，上面的函數UTF-16到UTF8，然后再進行Base64的編碼。

下面是關于Js進行Base64編碼和解碼的相關操作：

var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var base64DecodeChars = new Array(
??? -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
??? -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
??? -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
??? 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
??? -1,? 0,? 1,? 2,? 3,? 4,? 5,? 6,? 7,? 8,? 9, 10, 11, 12, 13, 14,
??? 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
??? -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
??? 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1);
//客戶端Base64編碼
function base64encode(str) {
??? var out, i, len;
??? var c1, c2, c3;

??? len = str.length;
??? i = 0;
??? out = "";
??? while(i < len) {
?c1 = str.charCodeAt(i++) & 0xff;
?if(i == len)
?{
???? out += base64EncodeChars.charAt(c1 >> 2);
???? out += base64EncodeChars.charAt((c1 & 0x3) << 4);
???? out += "==";
???? break;
?}
?c2 = str.charCodeAt(i++);
?if(i == len)
?{
???? out += base64EncodeChars.charAt(c1 >> 2);
???? out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
???? out += base64EncodeChars.charAt((c2 & 0xF) << 2);
???? out += "=";
???? break;
?}
?c3 = str.charCodeAt(i++);
?out += base64EncodeChars.charAt(c1 >> 2);
?out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
?out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6));
?out += base64EncodeChars.charAt(c3 & 0x3F);
??? }
??? return out;
}
//客戶端Base64解碼
function base64decode(str) {
??? var c1, c2, c3, c4;
??? var i, len, out;

??? len = str.length;
??? i = 0;
??? out = "";
??? while(i < len) {
?/* c1 */
?do {
???? c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
?} while(i < len && c1 == -1);
?if(c1 == -1)
???? break;

?/* c2 */
?do {
???? c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
?} while(i < len && c2 == -1);
?if(c2 == -1)
???? break;

?out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4));

?/* c3 */
?do {
???? c3 = str.charCodeAt(i++) & 0xff;
???? if(c3 == 61)
? return out;
???? c3 = base64DecodeChars[c3];
?} while(i < len && c3 == -1);
?if(c3 == -1)
???? break;

?out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2));

?/* c4 */
?do {
???? c4 = str.charCodeAt(i++) & 0xff;
???? if(c4 == 61)
? return out;
???? c4 = base64DecodeChars[c4];
?} while(i < len && c4 == -1);
?if(c4 == -1)
???? break;
?out += String.fromCharCode(((c3 & 0x03) << 6) | c4);
??? }
??? return out;
}

這樣傳遞過去的值就可以在服務器端解碼操作了。
下面是C#的Base64加碼和解碼的相關類：
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

namespace CNVP.Base64
{
??? /// <summary>
??? /// MyBase64 的摘要說明
??? /// </summary>
??? public class MyBase64
??? {
??????? public MyBase64()
??????? {
??????????? //
??????????? // TODO: 在此處添加構造函數邏輯
??????????? //
??????? }
??????? /// <summary>
??????? /// 服務器端Base64編碼
??????? /// </summary>
??????? /// <param name="data"></param>
??????? /// <returns></returns>
??????? public string base64Encode(string data)
??????? {
??????????? try
??????????? {
??????????????? byte[] encData_byte = new byte[data.Length];
??????????????? encData_byte = System.Text.Encoding.UTF8.GetBytes(data);
??????????????? string encodedData = Convert.ToBase64String(encData_byte);
??????????????? return encodedData;
??????????? }
??????????? catch (Exception e)
??????????? {
??????????????? throw new Exception("Error in base64Encode" + e.Message);
??????????? }
??????? }
??????? /// <summary>
??????? /// 服務器端Base64解碼
??????? /// </summary>
??????? /// <param name="data"></param>
??????? /// <returns></returns>
??????? public string base64Decode(string data)
??????? {
??????????? try
??????????? {
??????????????? System.Text.UTF8Encoding encoder = new System.Text.UTF8Encoding();
??????????????? System.Text.Decoder utf8Decode = encoder.GetDecoder();
??????????????? byte[] todecode_byte = Convert.FromBase64String(data);
??????????????? int charCount = utf8Decode.GetCharCount(todecode_byte, 0, todecode_byte.Length);
??????????????? char[] decoded_char = new char[charCount];
??????????????? utf8Decode.GetChars(todecode_byte, 0, todecode_byte.Length, decoded_char, 0);
??????????????? string result = new String(decoded_char);
??????????????? return result;
??????????? }
??????????? catch (Exception e)
??????????? {
??????????????? throw new Exception("Error in base64Decode" + e.Message);
??????????? }
??????? }
??? }
}

??????? var Keyword=base64encode(utf16to8(document.all.Keyword.value));
??????? Keyword=Keyword.replace("+","%2B");//替換+，否則在服務器解碼的時候會出錯
服務器端使用以下代碼調用：
??????????? CNVP.Base64.MyBase64 base64 = new CNVP.Base64.MyBase64();
??????????? Keyword=base64.base64Decode(Keyword);