C/C ++ string processing functions

When I first learned C/C ++, I had always been familiar with string processing functions. Here I will list C/C ++ string processing functions and hope they will be helpful to beginners.

C:

Char st [100];

1. String Length

Strlen (st );

2. String comparison

Strcmp (st1, st2 );

Strncmp (st1, st2, n); compare the first n of st1 and st2.

3. Add

Strcat (st1, st2 );

Strncat (st1, st2, n); n indicates the first n of st2 connected to st1. Do not add '/0' at the end '.

4. Replace

Strcpy (st1, st2 );

Strncpy (st1, st2, n); n indicates to copy the first n of st2 to st1 and add '/0' at the end '.

5. Search

Where = strchr (st, ch) ch is the character to be searched.

Where = strspns (st1, st2); search for strings.

C ++:

<String>

String str;

1. String Length

Len = str. length ();

Len = str. size ();

2. String comparison

Can be directly compared

You can also:

Str1.compare (str2 );

Str1.compare (pos1, len1, str2, pos2, len2); Value: Negative, 0, positive.

The nops length is reached.

3. Add

Str1 + = str2;

Or

Str1.append (str2 );

Str1.append (str2.pos2, len2 );

4. String Extraction

Str2 = str1.substr ();

Str2 = str1.substr (pos1 );

Str2 = str1.substr (pos1, len1 );

5. string SEARCH

Where = str1.find (str2 );

Where = str1.find (str2, pos1); pos1 starts from the nth digit of str1.

Where = str1.rfind (str2); search from the back.

6. Insert a string

It is not a value assignment statement.

Str1.insert (pos1, str2 );

Str1.insert (pos1, str2, pos2, len2 );

Str1.insert (pos1, numchar, char); numchar indicates the number of inserts and char indicates the characters to be inserted.

7. Replace string

Str1.replace (pos1, str2 );

Str1.replace (pos1, str2, pos2, len2 );

8. delete a string

Str. erase (pos, len)

Str. clear ();

9. Exchange strings

Swap (str1, str2 );

10. C --> C ++

Char * cstr = "Hello ";

String str1;

Cstr = cstr;

String str2 (cstr)