Objective-C字符串类NSString使用方法是本文要介绍的内容,内容不多,是用代码来讲解关于字符串的使用,不多说,来看内容。开发过程中,我们会遇到很多关于字符串的操作,它是一个常用的数据类型,下面对它的用法进行了汇总:
- //1、创建常量字符串。
- NSString *astring = @"This is a String!";
- //2、创建空字符串,给予赋值。
- NSString *astring = [[NSString alloc] init];
- astring = @"This is a String!";
- NSLog(@"astring:%@",astring);
- [astring release];
- //3、在以上方法中,提升速度:initWithString方法
- NSString *astring = [[NSString alloc] initWithString:@"This is a String!"];
- NSLog(@"astring:%@",astring);
- [astring release];
- //4、用标准c创建字符串:initWithCString方法
- char *Cstring = "This is a String!";
- NSString *astring = [[NSString alloc] initWithCString:Cstring];
- NSLog(@"astring:%@",astring);
- [astring release];
- //5、创建格式化字符串:占位符(由一个%加一个字符组成)
- int i = 1;
- int j = 2;
- NSString *astring = [[NSString alloc] initWithString:[NSString stringWithFormat:@"%d.This is %i string!",i,j]];
- NSLog(@"astring:%@",astring);
- [astring release];
- //6、创建临时字符串
- NSString *astring;
- astring = [NSString stringWithCString:"This is a temporary string"];
- NSLog(@"astring:%@",astring);
- NSString *path = @"astring.text";
- NSString *astring = [[NSString alloc] initWithContentsOfFile:path];
- NSLog(@"astring:%@",astring);
- [astring release];
- NSString *astring = [[NSString alloc] initWithString:@"This is a String!"];
- NSLog(@"astring:%@",astring);
- NSString *path = @"astring.text";
- [astring writeToFile: path atomically: YES];
- [astring release];
- //用C比较:strcmp函数
- char string1[] = "string!";
- char string2[] = "string!";
- if(strcmp(string1, string2) = = 0)
- {
- NSLog(@"1");
- }
- //isEqualToString方法
- NSString *astring01 = @"This is a String!";
- NSString *astring02 = @"This is a String!";
- BOOL result = [astring01 isEqualToString:astring02];
- NSLog(@"result:%d",result);
- //compare方法(comparer返回的三种值)
- NSString *astring01 = @"This is a String!";
- NSString *astring02 = @"This is a String!";
- BOOL result = [astring01 compare:astring02] = = NSOrderedSame;
- NSLog(@"result:%d",result);
- //NSOrderedSame 判断两者内容是否相同
- NSString *astring01 = @"This is a String!";
- NSString *astring02 = @"this is a String!";
- BOOL result = [astring01 compare:astring02] = = NSOrderedAscending;
- NSLog(@"result:%d",result);
- //NSOrderedAscending 判断两对象值的大小(按字母顺序进行比较,astring02大于astring01为真)
- NSString *astring01 = @"this is a String!";
- NSString *astring02 = @"This is a String!";
- BOOL result = [astring01 compare:astring02] = = NSOrderedDescending;
- NSLog(@"result:%d",result);
- //NSOrderedDescending 判断两对象值的大小(按字母顺序进行比较,astring02小于astring01为真)
- //不考虑大 小写比较字符串1
- NSString *astring01 = @"this is a String!";
- NSString *astring02 = @"This is a String!";
- BOOL result = [astring01 caseInsensitiveCompare:astring02] = = NSOrderedSame;
- NSLog(@"result:%d",result);
- //NSOrderedDescending判断两对象值的大小(按字母顺序进行比较,astring02小于astring01为真)
- //如何判断字符串为空
- NSString *urlString = [urlInput stringValue];
- if (!urlString) {
- NSLog( @”NO INPUT.” );
- } else {
- if ([urlString length] == 0 ) {
- NSLog( @”NO INPUT.” );
- } else {
- }
- }
- }
小结:详解Objective-C字符串类NSString使用方法的内容介绍完了,希望本文对你有所帮助!