c# - 在java中读取c#二进制文件

Question

我有一个 C# .net 程序，它使用 BinaryWriter.Write() 将 1 个整数和 3 个字符串写入文件。

现在我正在用 Java 编程(适用于 Android，我是 Java 的新手)，我必须访问以前使用 C# 写入文件的数据。

我尝试使用 DataInputStream.readInt() 和 DataInputStream.readUTF()，但无法获得正确的结果。我通常会得到一个 UTFDataFormatException:

java.io.UTFDataFormatException: malformed input around byte 21

或者我得到的 String 和 int 是错误的...

FileInputStream fs = new FileInputStream(strFilePath);
DataInputStream ds = new DataInputStream(fs);
int i;
String str1,str2,str3;
i=ds.readInt();
str1=ds.readUTF();
str2=ds.readUTF();
str3=ds.readUTF();
ds.close();

这样做的正确方法是什么？

Answer 1

我写了一个关于如何在 java 中读取 .net 的 binaryWriter 格式的快速示例 here

摘自链接:

   /**
 * Get string from binary stream. >So, if len < 0x7F, it is encoded on one
 * byte as b0 = len >if len < 0x3FFF, is is encoded on 2 bytes as b0 = (len
 * & 0x7F) | 0x80, b1 = len >> 7 >if len < 0x 1FFFFF, it is encoded on 3
 * bytes as b0 = (len & 0x7F) | 0x80, b1 = ((len >> 7) & 0x7F) | 0x80, b2 =
 * len >> 14 etc.
 *
 * @param is
 * @return
 * @throws IOException
 */
public static String getString(final InputStream is) throws IOException {
    int val = getStringLength(is);

    byte[] buffer = new byte[val];
    if (is.read(buffer) < 0) {
        throw new IOException("EOF");
    }
    return new String(buffer);
}

/**
 * Binary files are encoded with a variable length prefix that tells you
 * the size of the string. The prefix is encoded in a 7bit format where the
 * 8th bit tells you if you should continue. If the 8th bit is set it means
 * you need to read the next byte.
 * @param bytes
 * @return
 */
public static int getStringLength(final InputStream is) throws IOException {
    int count = 0;
    int shift = 0;
    boolean more = true;
    while (more) {
        byte b = (byte) is.read();
        count |= (b & 0x7F) << shift;
        shift += 7;
        if((b & 0x80) == 0) {
            more = false;
        }
    }
    return count;
}