Iphone 转换;“字符串”;将二进制文件转换为文本字符串
我能够将NSString(ASCII)文本转换为NSString(二进制数),但在做相反的事情时遇到困难。例如:“Hi”变为“01101000 011001” 我正在寻找最直接的方法来实现这一点。请注意每8位二进制数之间的空格。考虑到格式始终是这样的,此代码应该可以工作:Iphone 转换;“字符串”;将二进制文件转换为文本字符串,iphone,objective-c,binary,nsstring,ascii,Iphone,Objective C,Binary,Nsstring,Ascii,我能够将NSString(ASCII)文本转换为NSString(二进制数),但在做相反的事情时遇到困难。例如:“Hi”变为“01101000 011001” 我正在寻找最直接的方法来实现这一点。请注意每8位二进制数之间的空格。考虑到格式始终是这样的,此代码应该可以工作: NSString * BinaryToAsciiString (NSString *string) { NSMutableString *result = [NSMutableString string]; c
NSString *
BinaryToAsciiString (NSString *string)
{
NSMutableString *result = [NSMutableString string];
const char *b_str = [string cStringUsingEncoding:NSASCIIStringEncoding];
char c;
int i = 0; /* index, used for iterating on the string */
int p = 7; /* power index, iterating over a byte, 2^p */
int d = 0; /* the result character */
while ((c = b_str[i])) { /* get a char */
if (c == ' ') { /* if it's a space, save the char + reset indexes */
[result appendFormat:@"%c", d];
p = 7; d = 0;
} else { /* else add its value to d and decrement
* p for the next iteration */
if (c == '1') d += pow(2, p);
--p;
}
++i;
} [result appendFormat:@"%c", d]; /* this saves the last byte */
return [NSString stringWithString:result];
}
告诉我是否有部分不清楚。这是怎么回事
NSString* stringFromBinString(NSString* binString) {
NSArray *tokens = [binString componentsSeparatedByString:@" "];
char *chars = malloc(sizeof(char) * ([tokens count] + 1));
for (int i = 0; i < [tokens count]; i++) {
const char *token_c = [[tokens objectAtIndex:i] cStringUsingEncoding:NSUTF8StringEncoding];
char val = (char)strtol(token_c, NULL, 2);
chars[i] = val;
}
chars[[tokens count]] = 0;
NSString *result = [NSString stringWithCString:chars
encoding:NSUTF8StringEncoding];
free(chars);
return result;
}
NSString*stringFromBinString(NSString*binString){
NSArray*标记=[binString组件由字符串分隔:@”“];
char*chars=malloc(sizeof(char)*([tokens count]+1));
对于(int i=0;i<[令牌计数];i++){
const char*token_c=[[tokens objectAtIndex:i]cStringUsingEncoding:NSUTF8StringEncoding];
char val=(char)strtol(标记c,NULL,2);
chars[i]=val;
}
字符[[tokens count]]=0;
NSString*result=[NSString stringWithCString:chars
编码:NSUTF8StringEncoding];
免费(chars);
返回结果;
}
(以社区维基的形式发布-我以前的skool C技能已经过时了-请随意清理一下。:-)你有权使用C函数
strtoul
?很好!如果没有字符串分离的组件,这是不可能的:
@ap0stlex:很高兴它达到了您的要求。除了[result appendFormat:…]
,这只是由Objective-C包装的纯C。它可能具有多字节字符,但由于您使用ASCII,因此在C中很容易处理。
NSString* stringFromBinString(NSString* binString) {
NSArray *tokens = [binString componentsSeparatedByString:@" "];
char *chars = malloc(sizeof(char) * ([tokens count] + 1));
for (int i = 0; i < [tokens count]; i++) {
const char *token_c = [[tokens objectAtIndex:i] cStringUsingEncoding:NSUTF8StringEncoding];
char val = (char)strtol(token_c, NULL, 2);
chars[i] = val;
}
chars[[tokens count]] = 0;
NSString *result = [NSString stringWithCString:chars
encoding:NSUTF8StringEncoding];
free(chars);
return result;
}