Android 从网络中获取数据时 产生部分数据乱码的解决

转载请表明出处：http://blog.csdn.net/lmj623565791/article/details/23562939
问题描述：从网络中抓取html页面进行解析，解析后发现产生部分中文乱码。
由来：制作csdn客户端时产生 ， http://blog.csdn.net/lmj623565791/article/details/23532797 （java环境下，使用控制台打印出是没有乱码）



于是立马检查从服务器读取的代码：

[java] view plain copy print?<span style=“font-size:18px;”> /**
* 返回该链接地址的html数据
*
* @param urlStr
* @return
* @throws CommonException
*/
public static String doGet(String urlStr) throws CommonException
{
StringBuffer sb = new StringBuffer();
try
{
URL url = new URL(urlStr);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod(”GET”);
conn.setConnectTimeout(5000);
conn.setDoInput(true);
conn.setDoOutput(true);

if (conn.getResponseCode() == 200)
{
InputStream is = conn.getInputStream();
int len = 0;
byte[] buf = new byte[1024];

while ((len = is.read(buf)) != -1)
{
sb.append(new String(buf, 0, len, “UTF-8”));
}

is.close();
} else
{
throw new CommonException(“访问网络失败！”);
}

} catch (Exception e)
{
throw new CommonException(“访问网络失败！”);
}
return sb.toString();
}
</span>

/**
* 返回该链接地址的html数据
*
* @param urlStr
* @return
* @throws CommonException
*/
public static String doGet(String urlStr) throws CommonException
{
StringBuffer sb = new StringBuffer();
try
{
URL url = new URL(urlStr);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5000);
conn.setDoInput(true);
conn.setDoOutput(true);

if (conn.getResponseCode() == 200)
{
InputStream is = conn.getInputStream();
int len = 0;
byte[] buf = new byte[1024];

while ((len = is.read(buf)) != -1)
{
sb.append(new String(buf, 0, len, "UTF-8"));
}

is.close();
} else
{
throw new CommonException("访问网络失败！");
}

} catch (Exception e)
{
throw new CommonException("访问网络失败！");
}
return sb.toString();
}

发现可能是由于我采用字节流从网络读取数据，且每次读取1024个字节，读取完成后能后强制转化为字符串，又因为使用编码为UTF-8，UTF-8是一种变长码（英文1个字节，中文两个字节），所以1024可能会造成刚好截取了某个汉字的一半（前一个字节），然后转化为字符串时造成乱码。唯一不理解的在java环境下，使用控制台打印出是没有乱码的。如果你有不同的理解欢迎留言探讨。
于是把读取数据的代码从字节流改成字符流，修改后的代码为：

[java] view plain copy print?<span style=“font-size:18px;”> /**
* 返回该链接地址的html数据
*
* @param urlStr
* @return
* @throws CommonException
*/
public static String doGet(String urlStr) throws CommonException
{
StringBuffer sb = new StringBuffer();
try
{
URL url = new URL(urlStr);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod(”GET”);
conn.setConnectTimeout(5000);
conn.setDoInput(true);
conn.setDoOutput(true);

if (conn.getResponseCode() == 200)
{
InputStream is = conn.getInputStream();
InputStreamReader isr = new InputStreamReader(is,“UTF-8”);
int len = 0;
char[] buf = new char[1024];

while ((len = isr.read(buf)) != -1)
{
sb.append(new String(buf, 0, len));
}

is.close();
isr.close();
} else
{
throw new CommonException(“访问网络失败！”);
}

} catch (Exception e)
{
throw new CommonException(“访问网络失败！”);
}
return sb.toString();
}
</span>

/**
* 返回该链接地址的html数据
*
* @param urlStr
* @return
* @throws CommonException
*/
public static String doGet(String urlStr) throws CommonException
{
StringBuffer sb = new StringBuffer();
try
{
URL url = new URL(urlStr);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5000);
conn.setDoInput(true);
conn.setDoOutput(true);

if (conn.getResponseCode() == 200)
{
InputStream is = conn.getInputStream();
InputStreamReader isr = new InputStreamReader(is,"UTF-8");
int len = 0;
char[] buf = new char[1024];

while ((len = isr.read(buf)) != -1)
{
sb.append(new String(buf, 0, len));
}

is.close();
isr.close();
} else
{
throw new CommonException("访问网络失败！");
}

} catch (Exception e)
{
throw new CommonException("访问网络失败！");
}
return sb.toString();
}

问题解决。

转自:http://blog.csdn.net/lmj623565791/article/details/23562939