微信公众平台开发（六）翻译功能开发

上一篇文章介绍了微信公众平台天气预报功能的开发，实现了微信公众平台的第一个实际应用，在接下来的这一篇文章中，我们将对微信翻译功能进行简单开发，以供读者参考。

二、思路分析

和上一篇查询天气的思路差不多，首先要对用户发送过来的消息进行判断，判断消息里是否含有“翻译”关键字，如果含有，则提取待翻译内容，然后调用网络上开放的翻译API 进行相关翻译。

网络上有很多翻译API，大家可以根据自己的需求进行选择。这里我们选择应用比较广泛的，翻译功能还比较不错的有道翻译API 和百度翻译API，下面对这两种API的相关信息进行分析。

3.1 有道翻译API

3.1.1 API 地址：http://fanyi.youdao.com/openapi

注意：有道提供的API 接口，在下面的测试时，json 数据格式返回不正确，到网上查阅资料，可以正确翻译的地址为 http://fanyi.youdao.com/fanyiapi，这点注意。

3.1.2 申请key

按照要求填写相关信息，这些信息，下面会使用到，所以请认真如实填写。

申请完之后，会在下方生成API key 和keyfrom，使用API 时会用到。

3.1.3 API 使用范例

3.1.4 数据格式

a. xml 格式

http://fanyi.youdao.com/openapi.do?keyfrom=orchid&key=1008797533&type=data&doctype=&version=1.1&q=这里是有道翻译API

<span <?</span><span xml version="1.0" encoding="UTF-8"</span><span ?></span>
<span <</span><span youdao-fanyi</span><span ></span>
    <span <</span><span errorCode</span><span ></span>0<span </</span><span errorCode</span><span ></span>
    <span <!--</span><span  有道翻译 </span><span --></span>
    <span <</span><span query</span><span ></span><span <![CDATA[</span><span 这里是有道翻译API</span><span ]]></span><span </</span><span query</span><span ></span>
    <span <</span><span translation</span><span ></span>
        <span <</span><span paragraph</span><span ></span><span <![CDATA[</span><span Here is the youdao translation API</span><span ]]></span><span </</span><span paragraph</span><span ></span>
    <span </</span><span translation</span><span ></span>
<span </</span><span youdao-fanyi</span><span ></span>

로그인 후 복사

http://fanyi.youdao.com/openapi.do?keyfrom=orchid&key=1008797533&type=data&doctype=&version=1.1&q=翻译

<span {
    "errorCode":0
    "query":"翻译",
    "translation":["translation"], // 有道翻译
    "basic":{ // 有道词典-基本词典
        "phonetic":"fān y&igrave;",
        "explains":[
            "translate",
            "interpret"
        ]
    },
    "web":[ // 有道词典-网络释义
        {
            "key":"翻译",
            "value":["translator","translation","translate","Interpreter"]
        },
        {...}
    ]
}</span>

로그인 후 복사

3.2 百度翻译API

3.2.1 API 地址：http://openapi.baidu.com/public/2.0/bmt/translate

3.2.2 获取api key

开发者在百度连接平台上注册得到的授权API key，详细请参阅：http://developer.baidu.com/wiki/index.php?title=%E5%B8%AE%E5%8A%A9%E6%96%87%E6%A1%A3%E9%A6%96%E9%A1%B5/%E7%BD%91%E7%AB%99%E6%8E%A5%E5%85%A5/%E5%85%A5%E9%97%A8%E6%8C%87%E5%8D%97

3.2.3 API 使用范例

百度翻译API 响应的数据格式为UTF-8编码的PHP数组对应的标准JSON字符串。

<span {
    &ldquo;from&rdquo;:&rdquo;zh&rdquo;,
    &ldquo;to&rdquo;:&rdquo;en&rdquo;,
    &ldquo;trans_result&rdquo;:[]
}</span>

로그인 후 복사

trans_result 为一个数组，其中每一个{}就是一个段落，结构如下所示：

<span trans_result: [
{},
{},
{}
]</span>

로그인 후 복사

段落结果即为trans_result 数组中的一项：

<span {
&ldquo;src&rdquo;:&rdquo;&rdquo;,
&ldquo;dst&rdquo;:&rdquo;&rdquo;
}</span>

로그인 후 복사

段落结果说明：

经json_decode 后的形式：

<span {
    "from": "en",
    "to": "zh",
    "trans_result": [
        {
            "src": "today",
            "dst": "今天"
        }
    ]
}</span>

로그인 후 복사

翻译消息的格式是 “翻译+待翻译内容”，所以首先截取前两个字，判断是否为 “翻译” 关键字。

使用php函数 mb_substr() 截取，关于该函数的用法上一篇已经讲过，这里不再赘述。

从消息的开头开始截取，截取两个字符，然后加以判断是否为 “翻译” 关键字。

判断是否只输入“翻译”两字，这样输入，没有待翻译内容，则输入的消息也不正确。

接下来进行待翻译内容提取：

从消息的开头第3个字符开始截取，截取202个字符，截取出来的即为待翻译内容。

接着调用函数进行翻译。

<span //</span><span 调用有道词典</span>
<span $contentStr</span> = <span $this</span>->youdaoDic(<span $word</span><span );
</span><span //</span><span 调用百度词典</span>
<span $contentStr</span> = <span $this</span>->baiduDic(<span $word</span>);

로그인 후 복사

5.1 有道翻译API

数据接口：

http://fanyi.youdao.com/openapi.do?keyfrom=<span <</span><span keyfrom</span><span ></span><span &key</span>=<span <</span><span key</span><span ></span><span &type</span>=data<span &doctype</span>=<span <</span><span doctype</span><span ></span><span &version</span>=1.1<span &q</span>=要翻译的文本

로그인 후 복사

5.1.1 xml 格式

关键代码如下：

<span public</span> <span function</span> youdaoDic(<span $word</span><span ){

        </span><span $keyfrom</span> = "orchid";    <span //</span><span 申请APIKEY 时所填表的网站名称的内容</span>
        <span $apikey</span> = "YourApiKey";  <span //</span><span 从有道申请的APIKEY
        
        //有道翻译-xml格式</span>
        <span $url_youdao</span> = 'http://fanyi.youdao.com/fanyiapi.do?keyfrom='.<span $keyfrom</span>.'&key='.<span $apikey</span>.'&type=data&doctype=xml&version=1.1&q='.<span $word</span><span ;
        
        </span><span $xmlStyle</span> = <span simplexml_load_file</span>(<span $url_youdao</span><span );
        
        </span><span $errorCode</span> = <span $xmlStyle</span>-><span errorCode;

        </span><span $paras</span> = <span $xmlStyle</span>->translation-><span paragraph;

        </span><span if</span>(<span $errorCode</span> == 0<span ){
            </span><span return</span> <span $paras</span><span ;
        }</span><span else</span><span {
            </span><span return</span> "无法进行有效的翻译"<span ;
        }<br />}</span>

로그인 후 복사

说明：

$xmlStyle = simplexml_load_file($url_youdao);　　// PHP 函数，将XML 文档载入对象中。

$errorCode = $xmlStyle->errorCode;　　// 获取错误码

$paras = $xmlStyle->translation->paragraph;　　// 获取翻译内容

5.1.2 json 格式

关键代码如下：

    <span public</span> <span function</span> youdaoDic(<span $word</span><span ){

        </span><span $keyfrom</span> = "orchid";    <span //</span><span 申请APIKEY时所填表的网站名称的内容</span>
        <span $apikey</span> = "YourApiKey";  <span //</span><span 从有道申请的APIKEY
        
        //有道翻译-json格式</span>
        <span $url_youdao</span> = 'http://fanyi.youdao.com/fanyiapi.do?keyfrom='.<span $keyfrom</span>.'&key='.<span $apikey</span>.'&type=data&doctype=json&version=1.1&q='.<span $word</span><span ;
        
        </span><span $jsonStyle</span> = <span file_get_contents</span>(<span $url_youdao</span><span );

        </span><span $result</span> = json_decode(<span $jsonStyle</span>,<span true</span><span );
        
        </span><span $errorCode</span> = <span $result</span>['errorCode'<span ];
        
        </span><span $trans</span> = ''<span ;

        </span><span if</span>(<span isset</span>(<span $errorCode</span><span )){

            </span><span switch</span> (<span $errorCode</span><span ){
                </span><span case</span> 0:
                    <span $trans</span> = <span $result</span>['translation']['0'<span ];
                    </span><span break</span><span ;
                </span><span case</span> 20:
                    <span $trans</span> = '要翻译的文本过长'<span ;
                    </span><span break</span><span ;
                </span><span case</span> 30:
                    <span $trans</span> = '无法进行有效的翻译'<span ;
                    </span><span break</span><span ;
                </span><span case</span> 40:
                    <span $trans</span> = '不支持的语言类型'<span ;
                    </span><span break</span><span ;
                </span><span case</span> 50:
                    <span $trans</span> = '无效的key'<span ;
                    </span><span break</span><span ;
                </span><span default</span>:
                    <span $trans</span> = '出现异常'<span ;
                    </span><span break</span><span ;
            }
        }
        </span><span return</span> <span $trans</span><span ;
        
    }</span>

로그인 후 복사

说明：

把整个文件读入一个字符串中

$result = json_decode($jsonStyle,true);　　// 对JSON 格式的字符串进行编码

$errorCode = $result['errorCode'];　　// 获取错误码

$trans = $result['translation']['0'];　　// 获取翻译结果

5.2 百度翻译API

百度翻译API提供UTF-8编码的PHP数组对应的标准JSON字符串，而且提供了中->英，中->日，英->中，日->中四种互译，比有道翻译多了一种。

关键代码如下：

    <span //</span><span 百度翻译</span>
    <span public</span> <span function</span> baiduDic(<span $word</span>,<span $from</span>="auto",<span $to</span>="auto"<span ){
        
        </span><span //</span><span 首先对要翻译的文字进行 urlencode 处理</span>
        <span $word_code</span>=<span urlencode</span>(<span $word</span><span );
        
        </span><span //</span><span 注册的API Key</span>
        <span $appid</span>="<span YourApiKey</span>"<span ;
        
        </span><span //</span><span 生成翻译API的URL GET地址</span>
        <span $baidu_url</span> = "http://openapi.baidu.com/public/2.0/bmt/translate?client_id=".<span $appid</span>."&q=".<span $word_code</span>."&from=".<span $from</span>."&to=".<span $to</span><span ;
        
        </span><span $text</span>=json_decode(<span $this</span>->language_text(<span $baidu_url</span><span ));

        </span><span $text</span> = <span $text</span>-><span trans_result;

        </span><span return</span> <span $text</span>[0]-><span dst;
    }
        
    </span><span //</span><span 百度翻译-获取目标URL所打印的内容</span>
    <span public</span> <span function</span> language_text(<span $url</span><span ){

        </span><span if</span>(!<span function_exists</span>('file_get_contents'<span )){

            </span><span $file_contents</span> = <span file_get_contents</span>(<span $url</span><span );

        }</span><span else</span><span {
                
            </span><span //</span><span 初始化一个cURL对象</span>
            <span $ch</span> =<span  curl_init();

            </span><span $timeout</span> = 5<span ;

            </span><span //</span><span 设置需要抓取的URL</span>
            curl_setopt (<span $ch</span>, CURLOPT_URL, <span $url</span><span );

            </span><span //</span><span 设置cURL 参数，要求结果保存到字符串中还是输出到屏幕上</span>
            curl_setopt (<span $ch</span>, CURLOPT_RETURNTRANSFER, 1<span );

            </span><span //</span><span 在发起连接前等待的时间，如果设置为0，则无限等待</span>
            curl_setopt (<span $ch</span>, CURLOPT_CONNECTTIMEOUT, <span $timeout</span><span );

            </span><span //</span><span 运行cURL，请求网页</span>
            <span $file_contents</span> = curl_exec(<span $ch</span><span );

            </span><span //</span><span 关闭URL请求</span>
            curl_close(<span $ch</span><span );
        }

        </span><span return</span> <span $file_contents</span><span ;
    }</span>

로그인 후 복사

说明：

baiduDic() 函数：

language_text($baidu_url));　　// 调用language_text() 函数获取目标URL所打印的内容，然后对JSON 格式的字符串进行编码

trans_result;　　//获取翻译结果数组

dst;　　//取第一个数组的dst 结果。

language_text() 函数：

有道翻译-xml 格式：