[摘要]本文是對【代碼筆記】由身份證號碼返回性別的講解，對學習IOS蘋果軟件開發有所幫助,與大家分享。

一，代碼。

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    NSString *sex=[self sexStrFromIdentityCard:@"139876456767892345"];
    NSLog(@"--sex--%@",sex);
    
}
//由身份證號返回為性別
-(NSString *)sexStrFromIdentityCard:(NSString *)numberStr{
    NSString *result = nil;
    
    BOOL isAllNumber = YES;
    
    if([numberStr length]<17)
        return result;
    
    //**截取第17為性別識別符
    NSString *fontNumer = [numberStr substringWithRange:NSMakeRange(16, 1)];
    
    //**檢測是否是數字;
    const char *str = [fontNumer UTF8String];
    const char *p = str;
    while (*p!='\0') {
        if(!(*p>='0'&&*p<='9'))
            isAllNumber = NO;
        p++;
    }
    
    if(!isAllNumber)
        return result;
    
    int sexNumber = [fontNumer integerValue];
    if(sexNumber%2==1)
        result = @"男";
    ///result = @"M";
    else if (sexNumber%2==0)
        result = @"女";
    //result = @"F";
    
    return result;
    
    
}

二，輸出。

2015-10-22 10:33:38.518 由身份證號碼返回性別[2356:74542] --sex--女