What is the method of Java data conversion?
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1 convert string to data
Convert a string to an integer:
String MyNumber = "1234"
Int MyInt = Integer.parseInt (MyNumber)
String can be converted to byte, short, int, float, double, long and other data types.
To refer to the parseXXX of the Byte, Short, Integer, Float, Double, Long classes, respectively
Method.
2 convert data to string
Convert integers to strings:
Int MyInt = 1234
String MyString = "" + MyInt
Other data types can be converted to strings in the same way.
3 conversion from decimal to other decimal
Decimal integers are converted to binary integers, and the result is a string:
Integer.toBinaryString (int I)
Integer and Long provide toBinaryString, toHexString and toOctalString
Method, you can easily convert data into binary, hexadecimal, and octal strings. Function is more
The big enhancement is its toString (int/long I, int radix) method, which can put a decimal
The number is converted to an arbitrary string form.
Data types such as byte, short, float and double. You can use Integer or Long.
Conversion of toBinaryString, toHexString, to OctalString and toString methods based on
Into other binary string forms.
4 other decimal to decimal conversion
The pentadic string 14414 is converted to a decimal integer, and the result is 1234:
System.out.println (Integer.valueOf (14414), 5)
ValueOf (String source, int radix) methods provided by Integer and Long, you can
Converts an arbitrary string into decimal data.
5 conversion from integer to byte array
Public static byte [] toByteArray (int number)
{
Int temp = number
Byte [] b=new byte [4]
For (int I = b.length-1; I >-1; iMel -)
{
B [I] = new Integer (temp & 0xff) .byteValue ()
Temp = temp > > 8
}
Return b
}
Conversion from 6-byte array to integer
Public static int toInteger (byte [] b)
{
Int s = 0
For (int I = 0; I
< 3; i++) { if (b[i] >0)
S = s + b [I]
Else
S = s + 256 + b [I]
S = s * 256
}
If (b [3] > 0)
S = s + b [3]
Else
S = s + 256 + b [3]
Return s
}
7 conversion between short integers and byte arrays
The difference between short and int is that short is two bytes, while int is four bytes.
Therefore, short integers and bytes can be realized by making minor changes to the sample programs in 5 and 6.
The conversion between arrays.
Convert an 8-byte array to a double-precision floating-point number
Public double toDouble (byte [] b)
{
Long l = 0
Double D = new Double (0.0)
L = b [0]
L | = (long) b [1]
