NSString基础知识

目录

pragma mark - NSString基础

void testFirst(){    //        NSString是核心处理字符串的类之一         ALog(@"1、创建一个字符串");        NSString *aSing = [NSString new];        aSing = @"aSing";        NSLog(@"显示aSing：%@",aSing);        ALog(@"2、判断字符串(英文)长度");        ALog(@"aSing长度：%ld",[aSing length]);        ALog(@"3、判断字符串(中文)长度");        NSString *aSing2 = @"我们的祖国 ";        ALog(@"aSing2长度：%ld",[aSing2 length]);    //        在OC字符串中中英文都占一个字符        ALog(@"4、当字符串为空时");        NSString *djie ;        NSLog(@"djie == null  djie.length:%lu",(unsigned long)djie.length);}

pragma mark - 字符串比较

void testCompare(NSArray *array){        ALog(@"字符串比较");        ALog(@"取出每个字符串的ASCII码值进行相互比较大小,区分大小写");        NSComparisonResult result = [array[0] compare:array[1]];        ALog(@"显示NSComparisonResult：%ld",(long)result);        switch (result) {            case NSOrderedAscending: {    //            -1                ALog(@"后面的字符长度大于前面的");                break;            }            case NSOrderedSame: {    //            0                ALog(@"相等");                break;            }            case NSOrderedDescending: {    //            1                ALog(@"前面的字符长度大于后面的");                break;            }        }}

pragma mark - 比较字符串是否相等

void testCompare2(NSArray *array){    ALog(@"字符串比较是否相等");    ALog(@"取出每个字符串相互比较,区分大小写");    BOOL checkString = [array[0] isEqualToString:array[1]];    ALog(@"显示isEqualToString：%hhd",checkString);    if (checkString) {        ALog(@"%@两个字符串相同%@",array[0],array[1]);    } else {        ALog(@"%@两个字符串不相同%@",array[0],array[1]);    }}

pragma mark - 字符串前缀检查

void testHasPrefix(NSString *stringForHttp){    ALog(@"字符串前缀是否是http:");    ALog(@"检查字符串前缀是否包含“http”");    BOOL checkString = [stringForHttp hasPrefix:@"http:"];    ALog(@"显示hasPrefix：%hhd",checkString);    if (checkString) {        ALog(@"%@包含了http:",stringForHttp);    } else {        ALog(@"%@没包含http:",stringForHttp);    }}

pragma mark - 字符串后缀检查

void testHasSuffix(NSString *stringForHttp){    ALog(@"字符串后缀是否是png");    ALog(@"检查字符串后缀是否包含“png”");    BOOL checkString = [stringForHttp hasSuffix:@"png"];    ALog(@"显示hasSuffix：%hhd",checkString);    if (checkString) {        ALog(@"%@包含了png:",stringForHttp);    } else {        ALog(@"%@没包含png:",stringForHttp);    }}

pragma mark - 字符串查找定位

void testRangeOfString(NSString *stringForSearch){    ALog(@"字符串中是否包含某字符串，并确定初始位置");    ALog(@"");    NSString *stringForCertain = @"ios";    NSRange range = [stringForSearch rangeOfString:stringForCertain];    ALog(@"显示字符串“ios”首次在字符串中的位置：range.locations：%@",NSStringFromRange(range));    NSInteger allStringlength = [stringForSearch length];    if (allStringlength > range.location) {        ALog(@"查到了");    } else {        ALog(@"没查到");    }}

pragma mark - 以指定位置开始（包括指定位置的字符），并包括之后的全部字符

void testSubstringFromIndex(NSString *stringForSearch){    ALog(@"从from起始(包括起始)截取到到尾部");    NSString *subString = [stringForSearch substringFromIndex:3];    ALog(@"显示subString：%@",subString);}

pragma mark - 从字符串的开头一直截取到指定的位置，但不包括该位置的字符

void testSubstringToIndex(NSString *stringForSearch){    ALog(@"从起始(包括起始)截取到到from");    NSString *substringToIndex = [stringForSearch substringToIndex:3];    ALog(@"显示substringToIndex：%@",substringToIndex);}

pragma mark - 题目：将标签内的字符串取出来你好

void testSecond(){    //    将标签内的字符串取出来你好    ALog(@"将标签内的字符串取出来你好");    NSString *way = @"将标签内的字符串取出来你dauhdiuhwdihwudqw好";    NSRange range1 = [way rangeOfString:@""];    //    NSRange range2 = [way rangeOfString:@""];    //    NSInteger locationRange = range2.location - range1.location-8;    way = [way substringFromIndex:range1.location];    NSInteger lengthString = way.length - 8 - 9;    NSInteger locationString = 8;    way = [way substringWithRange:NSMakeRange(locationString, lengthString)];    ALog(@"显示way：%@",way);}

pragma mark - 替换–将*变为/

void testStringByReplacingOccurrencesOfString(NSString *stirngForSub){    NSString *subName = @"/";    ALog(@"1、显示修改前stirngForSub：%@",stirngForSub);    stirngForSub = [stirngForSub stringByReplacingOccurrencesOfString:@"*" withString:subName];    ALog(@"2、显示修改后stirngForSub：%@",stirngForSub);}

#pragma mark - 在指定位置插入字符串

void testInsertValue(NSString *stringForTest){//    NSString *insertValue = @"我们的祖国";//    [stringForTest insertValue:nil atIndex:2 inPropertyWithKey:insertValue];//    ALog(@"显示stringForTest：%@",stringForTest);}

pragma mark - 输出大写或者小写字符串，首字母显示

void testCaseString(){    NSString *test = @"qweqwweRtyRiopqwe";    ALog(@"显示原模板：%@",test);    ALog(@"显示字符大写：%@",[test uppercaseString]);    ALog(@"显示字符小写：%@",[test lowercaseString]);    ALog(@"显示首字母大写：%@",[test capitalizedString]);}

pragma mark - 分解成数组

void testComponentsSeparatedByString(){    ALog(@"将有规律的字符串分解");    ALog(@"asd|tes|mmm");    NSArray *array = [@"asd|tes|mmm" componentsSeparatedByString:@"|"];    ALog(@"array:%@",array);}

pragma mark - 主程序

int main(int argc, const char * argv[]) {    @autoreleasepool {        ALog(@"NSString大集合");//        testFirst();//        testCompare(@[@"123",@"qwe"]);//        testCompare2(@[@"QWE",@"qwe"]);//        testHasPrefix(@"http://www.baidu.com");//        testHasSuffix(@"jdiwjdoi.png");//        testRangeOfString(@"dedqiosdqoi");//        testSubstringToIndex(@"wangwenli");//        testSubstringFromIndex(@"wangwenli");//        testSecond();//        testStringByReplacingOccurrencesOfString(@"dqijd*q*wd*qiu*whdq");//        testCaseString();        testComponentsSeparatedByString();    }    return 0;}