How to Convert from Int to String

Java - Convert integer to string

There are multiple ways:

• String.valueOf(number) (my preference)
• "" + number (I don't know how the compiler handles it, perhaps it is as efficient as the above)
• Integer.toString(number)

Android how to convert int to String?

Use this String.valueOf(value);

How do I convert from int to String?

Normal ways would be Integer.toString(i) or String.valueOf(i).

The concatenation will work, but it is unconventional and could be a bad smell as it suggests the author doesn't know about the two methods above (what else might they not know?).

Java has special support for the + operator when used with strings (see the documentation) which translates the code you posted into:

StringBuilder sb = new StringBuilder();
sb.append("");
sb.append(i);
String strI = sb.toString();

at compile-time. It's slightly less efficient (sb.append() ends up calling Integer.getChars(), which is what Integer.toString() would've done anyway), but it works.

To answer Grodriguez's comment: ** No, the compiler doesn't optimise out the empty string in this case - look:

simon@lucifer:~$ cat TestClass.java
public class TestClass {
  public static void main(String[] args) {
    int i = 5;
    String strI = "" + i;
  }
}
simon@lucifer:~$ javac TestClass.java && javap -c TestClass
Compiled from "TestClass.java"
public class TestClass extends java.lang.Object{
public TestClass();
  Code:
   0:    aload_0
   1:    invokespecial    #1; //Method java/lang/Object."<init>":()V
   4:    return

public static void main(java.lang.String[]);
  Code:
   0:    iconst_5
   1:    istore_1

Initialise the StringBuilder:

   2:    new    #2; //class java/lang/StringBuilder
   5:    dup
   6:    invokespecial    #3; //Method java/lang/StringBuilder."<init>":()V

Append the empty string:

   9:    ldc    #4; //String
   11:    invokevirtual    #5; //Method java/lang/StringBuilder.append:
(Ljava/lang/String;)Ljava/lang/StringBuilder;

Append the integer:

   14:    iload_1
   15:    invokevirtual    #6; //Method java/lang/StringBuilder.append:
(I)Ljava/lang/StringBuilder;

Extract the final string:

   18:    invokevirtual    #7; //Method java/lang/StringBuilder.toString:
()Ljava/lang/String;
   21:    astore_2
   22:    return
}

There's a proposal and ongoing work to change this behaviour, targetted for JDK 9.

How to convert an int value to string in Go?

Easiest way to convert int to string in C++

C++11 introduces std::stoi (and variants for each numeric type) and std::to_string, the counterparts of the C atoi and itoa but expressed in term of std::string.

#include <string> 

std::string s = std::to_string(42);

is therefore the shortest way I can think of. You can even omit naming the type, using the auto keyword:

auto s = std::to_string(42);

Note: see [string.conversions] (21.5 in n3242)

How to convert an int to string in C?

EDIT: As pointed out in the comment, itoa() is not a standard, so better use sprintf() approach suggested in the rivaling answer!

---

You can use itoa() function to convert your integer value to a string.

Here is an example:

int num = 321;
char snum[5];

// convert 123 to string [buf]
itoa(num, snum, 10);

// print our string
printf("%s\n", snum);

---

If you want to output your structure into a file there is no need to convert any value beforehand. You can just use the printf format specification to indicate how to output your values and use any of the operators from printf family to output your data.

Dart convert int variable to string

Use toString and/or toRadixString

  int intValue = 1;
  String stringValue = intValue.toString();
  String hexValue = intValue.toRadixString(16);

or, as in the commment

  String anotherValue = 'the value is $intValue';

Convert int to string?

string myString = myInt.ToString();

Convert Int to String in Swift

Converting Int to String:

let x : Int = 42
var myString = String(x)

And the other way around - converting String to Int:

let myString : String = "42"
let x: Int? = myString.toInt()

if (x != nil) {
    // Successfully converted String to Int
}

Or if you're using Swift 2 or 3:

let x: Int? = Int(myString)

---

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