2017.4.18 string and int conversions in Java

1 How do I convert string strings to integer int?

A. There are two methods:

1). int i = Integer.parseint ([String]); Or

i = Integer.parseint ([string],[int radix]);

2). int i = integer.valueof (my_str). Intvalue ();

Note: The string is converted to Double, Float, and Long in a similar way.

2 How do I convert an integer int to a string string?

A. There are three ways:

1.) String s = string.valueof (i);

2.) String s = integer.tostring (i);

3.) String s = "" + I;

Note: Double, Float, Long turn into a string in a similar way.

int, String  
int i=12345; String s= ""; The first method: s=i+ ""; The second method: S=string.valueof (i); What is the difference between these two methods? Does it work the same? Are they interchangeable under any circumstances?
String, int  
s= "12345"; int i; First method: I=integer.parseint (s); second method: I= Integer.valueof (s). Intvalue (); What is the difference between these two methods? Does it work the same? Are they interchangeable under any circumstances?
Here's the answer:
The first method: s=i+ "";//generates two String objects the second method: S=string.valueof (i);//Use the static method of the String class only to produce an object
The first method: i= Integer.parseint (s);//Use static methods directly, do not produce extra objects, but throw exceptions the second method: I=integer.valueof (s). Intvalue ();//integer.valueof (s) equals The New Integer (Integer.parseint (s)) also throws an
exception, but produces more than one object
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1 How do I convert string strings to integer int?
A. There are two methods:
1). int i = Integer.parseint ([String]), or i = Integer.parseint ([string],[int radix]);
2). int i = integer.valueof (my_str). Intvalue ();
Note: The string turns into Double, Float, and Long in the same way. 2 How do I convert an integer int to a string string? A. There are three methods:
1.) String s = string.valueof (i);
2.) String s = integer.tostring (i);
3.) String s = "" + I;
Note: Double, Float, and Long turn into strings in a similar way.
Java data type conversion
Keyword    type conversion
This is an example of the conversion of data numbers in Java. For everyone to learn to lead

Package cn.com.lwkj.erts.register; Import Java.sql.Date; public class Typechange {public Typechange () {}//change the string type to the int type public static int Stringtoint (S     Tring intstr) {integer integer;     Integer = integer.valueof (INTSTR); return Integer.intvalue (); }//change int type to the string type public static string inttostring (int value) {integer integer = new Integer (val     UE); return integer.tostring ();     }//change the string type to the float type public static float Stringtofloat (string floatstr) {float floatee;     Floatee = float.valueof (FLOATSTR); return Floatee.floatvalue (); }//change the float type to the string type public static string floattostring (float value) {Float floatee = new Flo     at (value); return floatee.tostring (); }//change the string type to the Sqldate type public static Java.sql.Date stringtodate (string datestr) {return java. Sql. Date.valueof (DATESTR); }//change the Sqldate type to the string type publicStatic String datetostring (Java.sql.Date datee) {return datee.tostring ();} public static void Main (string[] args) {     Java.sql.Date Day;     Day = Typechange.stringtodate ("2003-11-3");     String strday = typechange.datetostring (day); System.out.println (Strday); } }

2017.4.18 string and int conversions in Java