C Tutorial/String/String Introduction
Содержание
A string is an array of characters.
#include <stdio.h>
int main(){
char myname[] = "Dan";
printf("%s \n",myname);
}Dan
String constants consist of text enclosed in double quotes
We must use the standard library function strcpy to copy the string constant into the variable.
To initialize the variable name to Sam.
#include <string.h>
int main()
{
char name[4];
strcpy(name, "Sam");
return (0);
}Strings
- A string is nothing more than a character array.
- All strings end with the NULL character.
- Use the %s placeholder in the printf() function to display string values.
#include <stdio.h>
main ( )
{
char *s1 = "abcd";
char s2[] = "efgh";
printf( "%s %16lu \n", s1, s1);
printf( "%s %16lu \n", s2, s2);
s1 = s2;
printf( "%s %16lu \n", s1, s1);
printf( "%s %16lu \n", s2, s2);
}abcd 4206592 efgh 2293584 efgh 2293584 efgh 2293584
Strings always end with the NULL character
ASCII code for the NULL character is \0
#include <stdio.h>
int main(){
char myname[4];
myname[0] = "D";
myname[1] = "a";
myname[2] = "n";
myname[3] = "\0";
printf("%s \n",myname);
}Dan
Useful string function
Function Description strcpy(string1, string2) Copy string2 into string1 strcat(string1, string2) Concatenate string2 onto the end of string1 length = strlen(string) Get the length of a string strcmp(string1, string2) 0 if string1 equals string2, otherwise nonzero
Write string in a more traditional array style
#include <stdio.h>
int main(){
char myname[] = { "D", "a", "n" };
printf("%s \n",myname);
}Dan?
