字符串大小寫轉換

_tcsupr函數  和_tcsdup

#include <string.h>
#include <stdio.h>

void main( void )
{
   char string[100] = "The String to End All Strings!";
   char *copy1, *copy2;
   copy1 = _strlwr( _strdup( string ) );
   copy2 = _strupr( _strdup( string ) );
   printf( "Mixed: %s/n", string );
   printf( "Lower: %s/n", copy1 );
   printf( "Upper: %s/n", copy2 );
}

Output
Mixed: The String to End All Strings!
Lower: the string to end all strings!
Upper: THE STRING TO END ALL STRINGS!

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