iOS 生成随机字符串 从指定字符串随机产生n个长度的新字符串
- 随机字符串 – 生成指定长度的字符串
-
-(NSString *)randomStringWithLength:(NSInteger)len {
-
NSString *letters = @”abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789″;
-
NSMutableString *randomString = [NSMutableString stringWithCapacity: len];
-
-
for (NSInteger i = 0; i < len; i++) {
-
[randomString appendFormat: @”%C”, [letters characterAtIndex: arc4random_uniform([letters length])]];
-
}
-
return randomString;
-
}
- 指定字符串随机生成指定长度的新字符串
-
-(NSString *)randomStringWithLength:(NSInteger)len String:(NSString *)letters {
-
-
NSMutableString *randomString = [NSMutableString stringWithCapacity: len];
-
-
for (NSInteger i = 0; i < len; i++) {
-
[randomString appendFormat: @”%C”, [letters characterAtIndex: arc4random_uniform([letters length])]];
-
}
-
return randomString;
-
}
-
//调用方法
-
-(NSString *)generateCard{
-
//HXMF 123456789TJQK
-
NSString *color =[self randomStringWithLength:1 String:@”HXMF”];
-
NSString *number = [self randomStringWithLength:1 String:@”123456789TJQK”];
-
return [NSString stringWithFormat:@”%@%@”,color,number];