Reverse hashcode to string (don't yell!)

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Hello,

I have a string str1 and I have got its hashcode.

I want to reverse it back to string like this:

string str1,hash1;
string str2;

str1="hello";

hash1=str1.GetHashcode();//no problem here

str2=hash1.Tostring();// could not find some thing like this
MessageBox("str1="+str1 +"IS SAME AS "+str2);

Posted 17-Aug-10 19:21pm

Khalid Sabtan

Updated 18-Aug-10 1:00am

Dalek Dave

v7

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Dalek Dave 18-Aug-10 7:01am

Minor Edit to Code Block

3 solutions

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**PSK_** · Answer 1 · 2010-08-17T19:34:00

Solution 1

GetHashCode() method return a numeric value and normally used for equality testing. In your case you are comparing a number and a string those can't be same.

And you should be get a typecasting error over here

hash1=str1.GetHashcode();//no problem here

Posted 17-Aug-10 19:34pm

PSK_

Comments

Khalid Sabtan 18-Aug-10 1:41am

str1="hellow"
assume that i have got hash1=1234567
how can i get str2=hellow

Christian Graus 18-Aug-10 2:05am

You can't. You should read a basic book and try to have some understanding of the tools you are using.

PSK_ 18-Aug-10 2:08am

You can't get the value back to "hellow" by the default GetHashCode() method. By the way why do you want to do this?

Khalid Sabtan 18-Aug-10 2:36am

//look at this
string str1="hellow"; char[] mychar=new char[6]; str1.CopyTo(0,mychar,0,6);
mychar[0] equal h i want to obtain the integer of mychar[0] assume it is 123 ,and it is stored in
int x like this x=convertFromcharToInteger (mychar[0]);
char[] my2ndchar=new char[5];
my2ndchar[0]=convertTochar(x);
my2ndchar[0] must be h <---this is my goal

Christian Graus · Answer 2 · 2010-08-17T20:04:00

Solution 3

You obviously don't understand what a hash is. If you did, you'd know that it's not possible to get a string from a hash.

Posted 17-Aug-10 20:04pm

Christian Graus

Khalid Sabtan · Answer 3 · 2010-08-18T02:16:00

ok i have got my goal without hashcode like this

C#

int i, j, k,len;
  long[] x = new long[128];
  char[] cc = new char[10];
  char[] cc2= new char[10];
  string str1 = "hellow",str2;
  len = str1.Length;
  str1.CopyTo(0, cc, 0, len);
  for (i = 0; i < len; i++)
  {
      x[i] = (int)cc[i];
      MessageBox.Show(x[i].ToString());
      x[i] = 2 * x[i] + 1;
  }
  str2 = "";char[] cc = new char[10];
  for (i = 0; i < len; i++)
  {
      x[i]=(x[i]-1)/2;
      cc2[i] = (char)x[i];
      MessageBox.Show(cc2[i].ToString());
      str2=str2+cc2[i];
  }
  MessageBox.Show(str2);