ASP.NET_各个币种之间的汇率转换（实时）使用Yahoo汇率。
近期开发支付平台的时候有运用到各国的实时汇率之间的转换问题，于是在往上找了很多相关资料，以下就是一些参考网址：
1、提供API接口的网站：https://www.showapi.com；这个网站有提供API的接口，本人换算了下与中国人民银行的汇算率相差不大。1万的换算率相差几块钱。（例：CNY（人民币）-->AUD（澳币））；
该网站提供的汇率换算结果是：1万人民币=1987.5579澳元；
中国人民银行换算结果是：1万人民币=1980.0100澳元；
（这个换算率是比较准确的，我是比较强烈的推荐使用这个API接口，由于个人只做笔记的问题，暂时还没研究这个API;）
2、谷歌汇率网站：http://www.google.com；这个网站我在测试的时候服务器没有连接通无法进行测试，也不清楚汇率到底是否准确。
3、雅虎汇率网站：http://finance.yahoo.com；这篇博客注重写的是这个网站的API接口，希望对大家开发有帮助，不过雅虎毕竟已经被Verizon收购了。服务器也是自然架设在国外，因此每个国家的汇率可能因此不同。测试的时候测试出汇率跟中国人民银行提供的还是差距蛮大的，因此本来是不想写出来的，但毕竟是花了时间编译 的，还是贴出来跟大家共享下。
该网站提供的汇率换算结果是：1万人民币=1940.00澳元；
中国人民银行换算结果是：1万人民币=1980.0100澳元；
看见了吗？差距1万元就会差了40元，oh my god！这个其实比起跨行转账手续费贵多了。所以是不推荐使用，只推荐学习。
准备材料：
1：页面准备：
1 <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ccYHOO.aspx.cs" Inherits="ExpressCheckout.ccYHOO" %> 2 3 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 4 5 <html xmlns="http://www.w3.org/1999/xhtml"> 6 <head id="Head1" runat="server"> 7 <title>Realtime Currency Converter ASP.NET Yahoo API</title> 8 <link rel="stylesheet" href="css/cc.css" /> 9 <script src="JQuery/jquery-1.7.2.min.js" type="text/javascript"></script> 10 <script src="JQuery/ccYHOO.js" type="text/javascript"></script> 11 </head> 12 <body> 13 <form id="form1" runat="server"> 14 <table class="main"> 15 <tr> 16 <th colspan="2"> 17 Realtime Currency Converter ASP.NET Yahoo API 18 </th> 19 </tr> 20 <tr> 21 <td> 22 Convert this amount 23 </td> 24 <td> 25 <input id="txtAmount" maxlength="12" size="5" value="1" class="controls" /> 26 </td> 27 </tr> 28 <tr> 29 <td> 30 From this currency: 31 </td> 32 <td> 33 <select id="drpFrom" class="controls"> 34 <option value="AED">United Arab Emirates Dirham (AED)</option> 35 <option value="ANG">Netherlands Antillean Guilder (ANG)</option> 36 <option value="ARS">Argentine Peso (ARS)</option> 37 <option value="AUD">Australian Dollar (AUD)</option> 38 <option value="BDT">Bangladeshi Taka (BDT)</option> 39 <option value="BGN">Bulgarian Lev (BGN)</option> 40 <option value="BHD">Bahraini Dinar (BHD)</option> 41 <option value="BND">Brunei Dollar (BND)</option> 42 <option value="BOB">Bolivian Boliviano (BOB)</option> 43 <option value="BRL">Brazilian Real (BRL)</option> 44 <option value="BWP">Botswanan Pula (BWP)</option> 45 <option value="CAD">Canadian Dollar (CAD)</option> 46 <option value="CHF">Swiss Franc (CHF)</option> 47 <option value="CLP">Chilean Peso (CLP)</option> 48 <option value="CNY">Chinese Yuan (CNY)</option> 49 <option value="COP">Colombian Peso (COP)</option> 50 <option value="CRC">Costa Rican Colón (CRC)</option> 51 <option value="CZK">Czech Republic Koruna (CZK)</option> 52 <option value="DKK">Danish Krone (DKK)</option> 53 <option value="DOP">Dominican Peso (DOP)</option> 54 <option value="DZD">Algerian Dinar (DZD)</option> 55 <option value="EEK">Estonian Kroon (EEK)</option> 56 <option value="EGP">Egyptian Pound (EGP)</option> 57 <option value="EUR">Euro (EUR)</option> 58 <option value="FJD">Fijian Dollar (FJD)</option> 59 <option value="GBP">British Pound Sterling (GBP)</option> 60 <option value="HKD">Hong Kong Dollar (HKD)</option> 61 <option value="HNL">Honduran Lempira (HNL)</option> 62 <option value="HRK">Croatian Kuna (HRK)</option> 63 <option value="HUF">Hungarian Forint (HUF)</option> 64 <option value="IDR">Indonesian Rupiah (IDR)</option> 65 <option value="ILS">Israeli New Sheqel (ILS)</option> 66 <option value="INR">Indian Rupee (INR)</option> 67 <option value="JMD">Jamaican Dollar (JMD)</option> 68 <option value="JOD">Jordanian Dinar (JOD)</option> 69 <option value="JPY">Japanese Yen (JPY)</option> 70 <option value="KES">Kenyan Shilling (KES)</option> 71 <option value="KRW">South Korean Won (KRW)</option> 72 <option value="KWD">Kuwaiti Dinar (KWD)</option> 73 <option value="KYD">Cayman Islands Dollar (KYD)</option> 74 <option value="KZT">Kazakhstani Tenge (KZT)</option> 75 <option value="LBP">Lebanese Pound (LBP)</option> 76 <option value="LKR">Sri Lankan Rupee (LKR)</option> 77 <option value="LTL">Lithuanian Litas (LTL)</option> 78 <option value="LVL">Latvian Lats (LVL)</option> 79 <option value="MAD">Moroccan Dirham (MAD)</option> 80 <option value="MDL">Moldovan Leu (MDL)</option> 81 <option value="MKD">Macedonian Denar (MKD)</option> 82 <option value="MUR">Mauritian Rupee (MUR)</option> 83 <option value="MVR">Maldivian Rufiyaa (MVR)</option> 84 <option value="MXN">Mexican Peso (MXN)</option> 85 <option value="MYR">Malaysian Ringgit (MYR)</option> 86 <option value="NAD">Namibian Dollar (NAD)</option> 87 <option value="NGN">Nigerian Naira (NGN)</option> 88 <option value="NIO">Nicaraguan Córdoba (NIO)</option> 89 <option value="NOK">Norwegian Krone (NOK)</option> 90 <option value="NPR">Nepalese Rupee (NPR)</option> 91 <option value="NZD">New Zealand Dollar (NZD)</option> 92 <option value="OMR">Omani Rial (OMR)</option> 93 <option value="PEN">Peruvian Nuevo Sol (PEN)</option> 94 <option value="PGK">Papua New Guinean Kina (PGK)</option> 95 <option value="PHP">Philippine Peso (PHP)</option> 96 <option value="PKR">Pakistani Rupee (PKR)</option> 97 <option value="PLN">Polish Zloty (PLN)</option> 98 <option value="PYG">Paraguayan Guarani (PYG)</option> 99 <option value="QAR">Qatari Rial (QAR)</option> 100 <option value="RON">Romanian Leu (RON)</option> 101 <option value="RSD">Serbian Dinar (RSD)</option> 102 <option value="RUB">Russian Ruble (RUB)</option> 103 <option value="SAR">Saudi Riyal (SAR)</option> 104 <option value="SCR">Seychellois Rupee (SCR)</option> 105 <option value="SEK">Swedish Krona (SEK)</option> 106 <option value="SGD">Singapore Dollar (SGD)</option> 107 <option value="SKK">Slovak Koruna (SKK)</option> 108 <option value="SLL">Sierra Leonean Leone (SLL)</option> 109 <option value="SVC">Salvadoran Colón (SVC)</option> 110 <option value="THB">Thai Baht (THB)</option> 111 <option value="TND">Tunisian Dinar (TND)</option> 112 <option value="TRY">Turkish Lira (TRY)</option> 113 <option value="TTD">Trinidad and Tobago Dollar (TTD)</option> 114 <option value="TWD">New Taiwan Dollar (TWD)</option> 115 <option value="TZS">Tanzanian Shilling (TZS)</option> 116 <option value="UAH">Ukrainian Hryvnia (UAH)</option> 117 <option value="UGX">Ugandan Shilling (UGX)</option> 118 <option value="USD">US Dollar (USD)</option> 119 <option value="UYU">Uruguayan Peso (UYU)</option> 120 <option value="UZS">Uzbekistan Som (UZS)</option> 121 <option value="VEF">Venezuelan Bolívar (VEF)</option> 122 <option value="VND">Vietnamese Dong (VND)</option> 123 <option value="XOF">CFA Franc BCEAO (XOF)</option> 124 <option value="YER">Yemeni Rial (YER)</option> 125 <option value="ZAR">South African Rand (ZAR)</option> 126 <option value="ZMK">Zambian Kwacha (ZMK)</option> 127 </select> 128 </td> 129 </tr> 130 <tr> 131 <td> 132 To this currency: 133 </td> 134 <td> 135 <select id="drpTo" class="controls"> 136 <option value="AED">United Arab Emirates Dirham (AED)</option> 137 <option value="ANG">Netherlands Antillean Guilder (ANG)</option> 138 <option value="ARS">Argentine Peso (ARS)</option> 139 <option value="AUD">Australian Dollar (AUD)</option> 140 <option value="BDT">Bangladeshi Taka (BDT)</option> 141 <option value="BGN">Bulgarian Lev (BGN)</option> 142 <option value="BHD">Bahraini Dinar (BHD)</option> 143 <option value="BND">Brunei Dollar (BND)</option> 144 <option value="BOB">Bolivian Boliviano (BOB)</option> 145 <option value="BRL">Brazilian Real (BRL)</option> 146 <option value="BWP">Botswanan Pula (BWP)</option> 147 <option value="CAD">Canadian Dollar (CAD)</option> 148 <option value="CHF">Swiss Franc (CHF)</option> 149 <option value="CLP">Chilean Peso (CLP)</option> 150 <option value="CNY">Chinese Yuan (CNY)</option> 151 <option value="COP">Colombian Peso (COP)</option> 152 <option value="CRC">Costa Rican Colón (CRC)</option> 153 <option value="CZK">Czech Republic Koruna (CZK)</option> 154 <option value="DKK">Danish Krone (DKK)</option> 155 <option value="DOP">Dominican Peso (DOP)</option> 156 <option value="DZD">Algerian Dinar (DZD)</option> 157 <option value="EEK">Estonian Kroon (EEK)</option> 158 <option value="EGP">Egyptian Pound (EGP)</option> 159 <option value="EUR">Euro (EUR)</option> 160 <option value="FJD">Fijian Dollar (FJD)</option> 161 <option value="GBP">British Pound Sterling (GBP)</option> 162 <option value="HKD">Hong Kong Dollar (HKD)</option> 163 <option value="HNL">Honduran Lempira (HNL)</option> 164 <option value="HRK">Croatian Kuna (HRK)</option> 165 <option value="HUF">Hungarian Forint (HUF)</option> 166 <option value="IDR">Indonesian Rupiah (IDR)</option> 167 <option value="ILS">Israeli New Sheqel (ILS)</option> 168 <option value="INR">Indian Rupee (INR)</option> 169 <option value="JMD">Jamaican Dollar (JMD)</option> 170 <option value="JOD">Jordanian Dinar (JOD)</option> 171 <option value="JPY">Japanese Yen (JPY)</option> 172 <option value="KES">Kenyan Shilling (KES)</option> 173 <option value="KRW">South Korean Won (KRW)</option> 174 <option value="KWD">Kuwaiti Dinar (KWD)</option> 175 <option value="KYD">Cayman Islands Dollar (KYD)</option> 176 <option value="KZT">Kazakhstani Tenge (KZT)</option> 177 <option value="LBP">Lebanese Pound (LBP)</option> 178 <option value="LKR">Sri Lankan Rupee (LKR)</option> 179 <option value="LTL">Lithuanian Litas (LTL)</option> 180 <option value="LVL">Latvian Lats (LVL)</option> 181 <option value="MAD">Moroccan Dirham (MAD)</option> 182 <option value="MDL">Moldovan Leu (MDL)</option> 183 <option value="MKD">Macedonian Denar (MKD)</option> 184 <option value="MUR">Mauritian Rupee (MUR)</option> 185 <option value="MVR">Maldivian Rufiyaa (MVR)</option> 186 <option value="MXN">Mexican Peso (MXN)</option> 187 <option value="MYR">Malaysian Ringgit (MYR)</option> 188 <option value="NAD">Namibian Dollar (NAD)</option> 189 <option value="NGN">Nigerian Naira (NGN)</option> 190 <option value="NIO">Nicaraguan Córdoba (NIO)</option> 191 <option value="NOK">Norwegian Krone (NOK)</option> 192 <option value="NPR">Nepalese Rupee (NPR)</option> 193 <option value="NZD">New Zealand Dollar (NZD)</option> 194 <option value="OMR">Omani Rial (OMR)</option> 195 <option value="PEN">Peruvian Nuevo Sol (PEN)</option> 196 <option value="PGK">Papua New Guinean Kina (PGK)</option> 197 <option value="PHP">Philippine Peso (PHP)</option> 198 <option value="PKR">Pakistani Rupee (PKR)</option> 199 <option value="PLN">Polish Zloty (PLN)</option> 200 <option value="PYG">Paraguayan Guarani (PYG)</option> 201 <option value="QAR">Qatari Rial (QAR)</option> 202 <option value="RON">Romanian Leu (RON)</option> 203 <option value="RSD">Serbian Dinar (RSD)</option> 204 <option value="RUB">Russian Ruble (RUB)</option> 205 <option value="SAR">Saudi Riyal (SAR)</option> 206 <option value="SCR">Seychellois Rupee (SCR)</option> 207 <option value="SEK">Swedish Krona (SEK)</option> 208 <option value="SGD">Singapore Dollar (SGD)</option> 209 <option value="SKK">Slovak Koruna (SKK)</option> 210 <option value="SLL">Sierra Leonean Leone (SLL)</option> 211 <option value="SVC">Salvadoran Colón (SVC)</option> 212 <option value="THB">Thai Baht (THB)</option> 213 <option value="TND">Tunisian Dinar (TND)</option> 214 <option value="TRY">Turkish Lira (TRY)</option> 215 <option value="TTD">Trinidad and Tobago Dollar (TTD)</option> 216 <option value="TWD">New Taiwan Dollar (TWD)</option> 217 <option value="TZS">Tanzanian Shilling (TZS)</option> 218 <option value="UAH">Ukrainian Hryvnia (UAH)</option> 219 <option value="UGX">Ugandan Shilling (UGX)</option> 220 <option value="USD">US Dollar (USD)</option> 221 <option value="UYU">Uruguayan Peso (UYU)</option> 222 <option value="UZS">Uzbekistan Som (UZS)</option> 223 <option value="VEF">Venezuelan Bolívar (VEF)</option> 224 <option value="VND">Vietnamese Dong (VND)</option> 225 <option value="XOF">CFA Franc BCEAO (XOF)</option> 226 <option value="YER">Yemeni Rial (YER)</option> 227 <option value="ZAR">South African Rand (ZAR)</option> 228 <option value="ZMK">Zambian Kwacha (ZMK)</option> 229 </select> 230 </td> 231 </tr> 232 <tr> 233 <td colspan="2" class="center"> 234 <input id="submit" type="button" value="Convert" /> 235 </td> 236 </tr> 237 <tr class="result"> 238 <td colspan="2" id="results" class="center"> 239 Result: .......... 240 </td> 241 </tr> 242 </table> 243 </form> 244 </body> 245 </html>
2：后台不需要写任何代码，完全是通过JS调用Webservice的;
3：需要添加两个关键的JS文件（ccYHOO.js和jquery-1.7.2.min.js）;
4：如果页面需要好看的话，那就多引用一个CSS文件；(css.cs);
这是下载地址： http://files.cnblogs.com/files/BarryJames/JQuery.zip（3-4的文件都在里面可自行下载）。
5：准备Webservice:代码如下
1 using System.Net; 2 using System.Text.RegularExpressions; 3 using System.Web.Script.Services; 4 namespace CurrencyConverter 5 { 6 /// <summary> 7 /// Summary description for WebService 8 /// </summary> 9 [WebService(Namespace = "http://tempuri.org/")] 10 [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] 11 [System.ComponentModel.ToolboxItem(false)] 12 [ScriptService] 13 public class WebService : System.Web.Services.WebService 14 { 15 [WebMethod] 16 public decimal ConvertYHOO(decimal amount, string fromCurrency, string toCurrency) 17 { 18 WebClient web = new WebClient(); 19 string url = string.Format("http://finance.yahoo.com/d/quotes.csv?e=.csv&f=sl1d1t1&s={0}{1}=X", fromCurrency.ToUpper(), toCurrency.ToUpper()); 20 string response = web.DownloadString(url); 21 string[] values = Regex.Split(response, ","); 22 decimal rate = System.Convert.ToDecimal(values[1]); 23 return rate * amount; 24 } 25 } 26 }
准备工作完成之后就可以开始调试了，调试的页面结果如下：
