How to override ToString of double?

Question

I want to override the function of a double how to do it?

for example:

double total=0.5;

string t=total.ToString();

I want it return a format that is specified.

Accepted Answer

If, after experimenting with the formats for ToString, you do not find any that satisfies your needs, then you can go back to the original question of "how to override ToString". Now, you cannot actually override it because overriding would require inheriting from double, which is not allowed. But you can instead create an extension method. You do that by adding a static method in a static class that takes "this double" as a parameter:

    public static class MyExtenders
    {
        public static string ToStringWithMyFormat(this double d)
        {
            string s = d.ToString(); // Make changes here to format d in whichever way you want it
            return s;
        }
    }

    // Use it like this:
    string t=total.ToStringWithMyFormat();

Answer

I'm not sure why you have a problem (or I'm don't understand why you're asking), you just put the format as a parameter in the .ToString().

double dbl = 0.5;
string dblString = dbl.ToString("0.00");
// some more examples:
dblString = dbl.ToString("F");
dblString = dbl.ToString("0.#");
dblString = dbl.ToString("0.##");
dblString = dbl.ToString("N");
dblString = dbl.ToString("N2");
dblString = dbl.ToString("N4");

Is that what you're asking about?

~~Bonnie DeWitt [MVP since 2003]
[http://geek-goddess-bonnie.blogspot.com]1

Answer

According to tutorialspoints
The java.lang.Double.toString() method returns a string representation of this Double object.
Below is complete demonstrations

package com.tutorialspoint;

import java.lang.*;

public class DoubleDemo {

public static void main(String[] args) {

  Double d = new Double("5.3");

  // returns a string representation
  String retval = d.toString();
  System.out.println("Value = " + retval);

}
}

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How to override ToString of double?

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