@import url(http://i.cnblogs.com/Load.ashx?type=style&file=SyntaxHighlighter.css);@import url(/css/cuteeditor.css);
@import url(http://i.cnblogs.com/Load.ashx?type=style&file=SyntaxHighlighter.css);@import url(/css/cuteeditor.css);
int age = 20;
NSRange range = NSMakeRange(1, 3);
// 类方法创建字符串
// 格式化字符串
NSString *str1 = [NSString stringWithFormat:@"Jack‘s age is %i",age];
NSString *str2 = [NSString stringWithString:str1];
NSString *str3 = [NSString stringWithContentsOfFile:@"/Users/Frozen/Downloads/1.txt" encoding:NSUTF8StringEncoding error:nil];
NSString *str4 = [NSString stringWithContentsOfURL:@"file:///Users/Frozen/Downloads/1.txt" encoding:NSUTF8StringEncoding error:nil];
// 生成空字符串
NSString *str5 = [NSString string];
// c语言字符串转换为oc字符串
NSString *st1 = [NSString stringWithUTF8String:"ji2"];
// 对象方法申请并初始化字符串
NSString *str6 = [[NSString alloc] initWithString:str1];
NSString *str7 = [[NSString alloc] initWithFormat:@"Jack‘s age is %i",age];
NSString *str8 = [[NSString alloc] initWithContentsOfFile:@"/Users/Frozen/Downloads/1.txt" encoding:NSUTF8StringEncoding error:nil];
NSString *str9 = [[NSString alloc] initWithContentsOfURL:@"file:///Users/Frozen/Downloads/1.txt" encoding:NSUTF8StringEncoding error:nil];
NSString *st2 = [[NSString alloc] initWithUTF8String:"jje"];
// 返回str1后面接@“Make”的新的字符串
NSString * str17 = [str1 stringByAppendingString:@"Make"];
// 返回i位置的字符
unichar c = [str2 characterAtIndex:2];
// 返回从index到字符串结尾的新的字符串
NSString *str10 = [str1 substringFromIndex:3];
// 返回从字符串开始到index的新的字符串
NSString *str11 = [str1 substringToIndex:4];
// 返回range范围内的新的字符串
NSString *str12 = [str1 substringWithRange:range];
//字符串比较
NSComparisonResult result = [str1 compare:str2 options:NSNumericSearch];
// result == NSOrderAscengding str1 < str2
// result == NSOrderSame str1 == str2
// result == NSOrderDescending str1 > str2
//options 掩码
// options: NSCaseInsensitiveSearch 不区分大小写
// options: NSLiteralSearch 完全比较，区分大小写
// options: NSNumericSearch 比较字符串的字符个数
// 是否以字符串@“Jack”开头
BOOL k = [str1 hasPrefix:@"Jack"];
// 是否以@“20”结尾
BOOL l = [str1 hasSuffix:@"20"];
// 字符串str1与str2是否相等
BOOL m = [str1 isEqualTo:str2];
// 返回全部转换为小写的新的字符串
NSString *str13 = [str1 lowercaseString];
// 返回全部转换为大写的新的字符串
NSString *str14 = [str1 uppercaseString];
// 返回首字母大写的新的字符串
NSString *str15 = [str1 capitalizedString];
// 将oc字符串转换为c语言字符串
const char *s = [str1 UTF8String];
// 字符串转换为基本数据类型
double d = [str1 doubleValue];
float f = [str1 floatValue];
int n = [str1 integerValue];
// 常见的NSMutableString方法
// 类方法
NSMutableString *mstr1 = [NSMutableString stringWithCapacity:5];
// 对象方法
NSMutableString *mstr2 = [[NSMutableString alloc] initWithCapacity:5];
// 以下方法返回对象本身
// 为用str1为字符串赋值
[mstr1 setString:str1];
// 为字符串后添加@“Miss”
[mstr1 appendString:@"Miss"];
// 删除某范围内的字符串
[mstr1 deleteCharactersInRange:range];
// 在index位置插入字符串@“cc”
[mstr1 insertString:@"cc" atIndex:2];
// 用Str1替换某范围内的字符串
[mstr1 replaceCharactersInRange:range withString:str1];