Integer.parseInt("12");是对的,这样返回一个int类型。Integer i=new Integer("12");返回的是int类型的wrapper class :Integer这样做就大错特错了
int i=(new Integer("12")).intValue();
integer to String : int i = 42; String str = Integer.toString(i); or String str = "" + idouble to String : String str = Double.toString(i);long to String : String str = Long.toString(l);float to String : String str = Float.toString(f); String to integer : str = "25"; int i = Integer.valueOf(str).intValue(); or int i = Integer.parseInt(str);String to double : double d = Double.valueOf(str).doubleValue();String to long : long l = Long.valueOf(str).longValue(); or long l = Long.parseLong(str);String to float : float f = Float.valueOf(str).floatValue();decimal to binary : int i = 42; String binstr = Integer.toBinaryString(i);decimal to hexadecimal : int i = 42; String hexstr = Integer.toString(i, 16); or String hexstr = Integer.toHexString(i);hexadecimal (String) to integer : int i = Integer.valueOf("B8DA3", 16).intValue(); or int i = Integer.parseInt("B8DA3", 16); ASCII code to String int i = 64; String aChar = new Character((char)i).toString(); integer to ASCII code (byte) char c = 'A'; int i = (int) c; // i will have the value 65 decimal To extract Ascii codes from a String String test = "ABCD"; for ( int i = 0; i < test.length(); ++i ) { char c = test.charAt( i ); int i = (int) c; System.out.println(i); } integer to boolean b = (i != 0);boolean to integer i = (b)?1:0;note :To catch illegal number conversion, try using the try/catch mechanism. try{ i = Integer.parseInt(aString); } catch(NumberFormatException e) { }
String str = Integer.toString(i);
or
String str = "" + idouble to String : String str = Double.toString(i);long to String : String str = Long.toString(l);float to String : String str = Float.toString(f);
String to integer : str = "25";
int i = Integer.valueOf(str).intValue();
or
int i = Integer.parseInt(str);String to double : double d = Double.valueOf(str).doubleValue();String to long : long l = Long.valueOf(str).longValue();
or
long l = Long.parseLong(str);String to float : float f = Float.valueOf(str).floatValue();decimal to binary : int i = 42;
String binstr = Integer.toBinaryString(i);decimal to hexadecimal : int i = 42;
String hexstr = Integer.toString(i, 16);
or
String hexstr = Integer.toHexString(i);hexadecimal (String) to integer : int i = Integer.valueOf("B8DA3", 16).intValue();
or
int i = Integer.parseInt("B8DA3", 16); ASCII code to String int i = 64;
String aChar = new Character((char)i).toString();
integer to ASCII code (byte) char c = 'A';
int i = (int) c; // i will have the value 65 decimal
To extract Ascii codes from a String String test = "ABCD";
for ( int i = 0; i < test.length(); ++i ) {
char c = test.charAt( i );
int i = (int) c;
System.out.println(i);
}
integer to boolean b = (i != 0);boolean to integer i = (b)?1:0;note :To catch illegal number conversion, try using the try/catch mechanism. try{
i = Integer.parseInt(aString);
}
catch(NumberFormatException e)
{
}