NSString与NSMutableString字符串操作：增、删、改字符串

NSString是定义固定大小的字符串，NSMutableString可变，可对字符串做增、删、改、插入等操作。

源代码strings.m

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#import <Foundation/Foundation.h>

int main (int argc, const char * argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

    // insert code here...
    NSString *artist = @"Underworld";
NSLog(@"The \"%@\" length is %d",artist,[artist length]);

NSString *substring = [artist substringFromIndex:5];

    NSLog(@"From index 5 to end that substring is \"%@\"",substring);

NSRange range = [artist rangeOfString:@"w"];
NSLog(@"range.location = %d,是字母\"w\"所在的索引位置",range.location);
NSLog(@"range.length = %d,是字母\"w\"的长度",range.length);

NSLog(@"------------------------------");

NSString *song = @"美丽新世界,伍佰";
NSRange range1 = [song rangeOfString:@","];
NSString *songName = [song substringToIndex:range1.location];
NSString *songAuthor = [song substringFromIndex:range1.location + range1.length]; //如果不加上range1.length,取词就包含逗号

NSLog(@"歌曲:%@",song);
NSLog(@"\",\"号位置为 %d",range1.location);
NSLog(@"歌名:%@",songName);
//printf("歌名:%s \n",[songName UTF8String]);//正确
//NSLog(@"歌名:%@", [songName UTF8String]);//错误
NSLog(@"作者:%@",songAuthor);

NSLog(@"---------------------------------");
NSLog(@"可变字符串类NSMultableString演示:");

NSMutableString *movie = [[NSMutableString alloc] initWithString:@"变形金刚2"];

NSLog(@"%@",movie);

[movie appendString:@",派拉蒙影业"];
NSLog(@"%@.方法appendString",movie);

NSRange range2 = [movie rangeOfString:@"派拉蒙影业"];
[movie replaceCharactersInRange:range2 withString:@"派拉蒙电影公司"]; //不是range2.location
NSLog(@"%@.方法replaceCharactersInRange",movie);

[movie deleteCharactersInRange:[movie rangeOfString:@"公司"]];
NSLog(@"%@.方法deleteCharactersInRange",movie);

    range2 = [movie rangeOfString:@"变形金刚"];
[movie insertString:@"科幻电影:" atIndex:range2.location];
NSLog(@"%@.方法insertString",movie);

[movie release]; //采用alloc的对象都不要忘记release
[pool drain];
    return 0;
}