java基本数据类型的转换

package day15;

public class StringAndNumber {

public static void main(String[] args) {

System.out.println("----------------int变String--------------------");
//int变String
int number=123456;
String IntToString1=String.valueOf(number);
System.out.println("int变String的方法1："+IntToString1);
String IntToString2=Integer.toString(number);
System.out.println("int变String的方法2："+IntToString2);

System.out.println("\n");
System.out.println("----------------double变String--------------------");
//double变String
double doubleNumber=123.456;
String doubelToString1=String.valueOf(doubleNumber);
System.out.println("double变String的方法1："+doubelToString1);
String doubelToString2=Double.toString(doubleNumber);
System.out.println("double变String的方法2："+doubelToString2);

System.out.println("\n");
System.out.println("----------------boolean变String--------------------");
//boolean变String
boolean booleanNumber=true;
String booleanToString1=String.valueOf(String.valueOf(booleanNumber));
System.out.println("boolean变String的方法1："+booleanToString1);
String booleanToString2= Boolean.toString(booleanNumber);
System.out.println("boolean变String的方法2："+booleanToString2);

System.out.println("\n");
System.out.println("----------------char变String--------------------");
//char变String
char charNumber='字';
String charToString1=String.valueOf(charNumber);
System.out.println("char变String的方法1："+charToString1);
String charToString2=Character.toString(charNumber);
System.out.println("char变String的方法2："+charToString2);

System.out.println("\n");
System.out.println("----------------String变int--------------------");
//String变int
String stringInt="123456";
int stringToInt=Integer.parseInt(stringInt);
System.out.println("String变int1:"+stringToInt);

int stringToInt2 = Integer.valueOf(stringInt).intValue();
System.out.println("String变int2:"+stringToInt2);

System.out.println("\n");
System.out.println("----------------String变double--------------------");
//String变double
String stringDouble="123.456";
double stringToDouble=Double.parseDouble(stringDouble);
System.out.println("String变double:"+stringToDouble);

System.out.println("\n");
System.out.println("----------------String变boolean--------------------");
//String变double
String stringBoolean="true";
boolean stringToBoolean=Boolean.parseBoolean(stringBoolean);
if(stringToBoolean){
System.out.println("String变boolean:"+stringToBoolean);
}

System.out.println("\n");
System.out.println("----------------String变Byte--------------------");
//String变double
String stringByte="0101";
Byte stringToByte=Byte.parseByte(stringByte);
System.out.println("String变Byte:"+stringToByte);

System.out.println("\n");
System.out.println("----------------String变char--------------------");
//String变double
String stringChar="中";
char stringToChar=stringChar.charAt(0);
System.out.println("String变char:"+stringChar);


System.out.println("\n");
System.out.println("----------------byte[]数组定义--------------------");
//现在我有一个Byte[]
byte[] bs = new byte[]{10,21,32,24,15};
for(int i=0;i<bs.length;i++){
System.out.println("byte数组第"+i+"个"+bs[i]);
}

System.out.println("\n");
System.out.println("----------------char变int--------------------");
//char转int方法 1:
char charVal = '9';
char[] charArray = {charVal};
int charToInt = Integer.parseInt(new String(charArray));
System.out.println("char转int方法 1: " + charVal + ":" + charToInt);

//char转int方法 2:
int charToInt2=Character.getNumericValue(charVal);
System.out.println("char转int方法 2: " + charVal + ":" + charToInt2);

System.out.println("\n");
System.out.println("----------------int变char--------------------");
//int转char的方法1
int i =8;
char c1 = Character.forDigit(i,10);
System.out.println("int: "+i+"转char的方法1: "+c1);
// System.out.println('');//编译错误，空字面量
int j =8;
char c2 = String.valueOf(i).charAt(0);
System.out.println("int: "+i+"转char的方法2 : "+c2);

System.out.println("\n");
System.out.println("----------------byte变int--------------------");
//现在我有一个Byte[]
byte b =6;
int byte2int=b;
System.out.println("byte2int:"+byte2int);

System.out.println("\n");
System.out.println("----------------int变byte--------------------");
//现在我有一个Byte[]
int intV =9;
byte int2byte=(byte)intV;
System.out.println("int2byte:"+int2byte);



}
}

转载于:https://www.cnblogs.com/jareny/p/10344079.html