一、Foundation框架中一些常用的类
字符串型:
NSString:不可变字符串
NSMutableString:可变字符串
集合型:
1)
NSArray:OC不可变数组
NSMutableArray:可变数组
2)
NSSet:
NSMutableSet:
3)
NSDictiorary
NSMutableDictiorary
其它:
NSDate
NSObject
二、NSString和NSMutableString的使用与注意
(一)6种创建字符串的形式
(二)使用注意
(1)字符串的导入导出
(2)类方法
(三)NSMutableString的使用与注意
(四)URL补充内容
Url:资源路径
格式:协议头:/路径
网络路径协议头:http
本地文件以file为协议头
ftp为协议头,说明资源是ftp服务器上的。
(四)字符串操作补充
1 #import <Foundation/Foundation.h> 2 3 int main(int argc, const char * argv[]) { 4 @autoreleasepool { 5 // insert code here... 6 // NSLog(@"Hello, World!"); 7 8 /* 9 不可变字符串 10 1.创建字符串 11 实例方法(3种) 12 类方法(3种) 13 2.不可变字符串: 14 统计长度(2种) 15 索引提取 (3种) 16 比较 (3种) 17 查照字符串位置(1种) 18 判断前后缀 19 转换数字 20 大小写转换 21 字符串提取 22 23 可变字符串 24 1.创建可变字符串 25 2.可变字符串的操作 26 增(3种)删(1种)改(1种)查 27 28 29 */ 30 31 //实例方法(3种) 32 NSString *str1 = @"123456789"; 33 NSString *str2 = [[NSString alloc] initWithFormat:@"%d4567",3]; 34 // NSString *str3 = [[NSString alloc] initWithString:str2];//传的是对象 35 36 //类方法(3种) 37 NSString *str4 = [NSString stringWithFormat:@"Abc%@eFg",@"d"]; 38 // NSString *str5 = [NSString stringWithString:str4]; 39 40 41 42 //统计长度(2种) 43 NSUInteger length = [str1 length]; 44 NSUInteger length1 = str1.length; 45 NSLog(@"%lu %lu",length,length1); 46 47 48 //索引提取 (3种) 49 NSString *newStr1 = [str1 substringFromIndex:3]; 50 NSLog(@"%@",newStr1); 51 NSString *newStr2 = [str1 substringToIndex:3]; 52 NSLog(@"%@",newStr2); 53 NSString *newStr3 = [str1 substringWithRange:NSMakeRange(3, 4)]; 54 NSLog(@"%@",newStr3);
NSString *string = [[NSString alloc] initWithFormat:@"%@",@"qwert"];
unichar ch =[string characterAtIndex:2];//提取字符串中的一个字符变成字符
NSLog(@"%c",ch);
55 56 57 //比较 (3种) 58 if ([str1 isEqualToString:str2]) { 59 NSLog(@"相同"); 60 }else 61 NSLog(@"不相同"); 62 63 64 65 if ([str1 compare:str2] == NSOrderedAscending) { 66 NSLog(@"str1>str2"); 67 } 68 else if ([str1 compare:str2] == NSOrderedDescending) 69 NSLog(@"str1<str2"); 70 else if ([str1 compare:str2] == NSOrderedSame) 71 NSLog(@"=="); 72 73 74 75 if ([str1 caseInsensitiveCompare:str2] == NSOrderedAscending) { 76 NSLog(@"str1>str2"); 77 } 78 else if ([str1 caseInsensitiveCompare:str2] == NSOrderedDescending) 79 NSLog(@"str1<str2"); 80 else if ([str1 caseInsensitiveCompare:str2] ==NSOrderedSame) 81 NSLog(@"=="); 82 83 84 // 查找字符串位置 85 NSRange range = [str1 rangeOfString:str2]; 86 if (range.location != NSNotFound) { 87 NSLog(@"location:%lu length:%lu",range.location,range.length); 88 89 } else { 90 NSLog(@"没找到"); 91 } 92 93 94 //判断前后缀(2种) 95 BOOL flag = [str4 hasPrefix:@"abc"]; 96 NSLog(@"%d",flag); 97 98 BOOL anotherFlag = [str4 hasSuffix:@"fg"]; 99 NSLog(@"%d",anotherFlag); 100 101 102 //转换数字(4种) 103 int number = [str1 intValue]; 104 NSLog(@"%d",number); 105 106 NSInteger number1 = [str1 intValue]; 107 NSLog(@"%ld",number1); 108 109 NSString *str6 = @"1234567.89"; 110 double number2 = [str6 doubleValue]; 111 NSLog(@"%lf",number2); 112 113 //大小写转换 114 NSString *upStr = [str4 uppercaseString]; 115 NSLog(@"%@",upStr); 116 NSString *lowStr = [str4 lowercaseString]; 117 NSLog(@"%@",lowStr); 118 NSString *tempStr = [str4 capitalizedString]; 119 NSLog(@"%@",tempStr); 120 121 122 123 124 // 可变字符串 125 // 实例方法 126 NSMutableString *muStr1 = [[NSMutableString alloc] 127 initWithFormat:@"1%d3",2]; 128 129 NSMutableString *muStr2 = [[NSMutableString alloc] 130 initWithString:@"123"]; 131 132 NSMutableString *muStr3 = [[NSMutableString alloc] 133 initWithCapacity:10]; 134 135 // 类方法 136 NSMutableString *muStr4 = [NSMutableString stringWithFormat:@"4%d6",5]; 137 138 NSMutableString *muStr5 = [NSMutableString stringWithString:@"123"]; 139 140 NSMutableString *muStr6 = [NSMutableString stringWithCapacity:10]; 141 142 143 //增(3种) 144 [muStr1 appendFormat:@"%d",456]; 145 NSLog(@"%@",muStr1); 146 147 [muStr2 appendString:@"789"]; 148 NSLog(@"%@",muStr2); 149 150 [muStr3 insertString:@"abcdefghijklmn" atIndex:0]; 151 NSLog(@"%@",muStr3); 152 153 [muStr4 insertString:@"abcdefghijklmn" atIndex:2]; 154 NSLog(@"%@",muStr4); 155 156 157 158 //删除 159 [muStr5 deleteCharactersInRange:NSMakeRange(2, 1)]; 160 NSLog(@"%@",muStr5); 161 162 //改 163 [muStr6 replaceCharactersInRange:NSMakeRange(0, 0) withString:@"1234567890"]; 164 NSLog(@"%@",muStr6); 165 166 [muStr5 replaceCharactersInRange:NSMakeRange(0, 1) withString:@"abcd"]; 167 NSLog(@"%@",muStr5); 168 169 } 170 return 0; 171 }