传递(指向UInt8数组的指针)并访问Objective-C中的数组

时间:2013-02-20 19:03:48

标签: java iphone objective-c xcode

我需要使用UInt8数组,但我不确定如何正确执行此操作...

这是我的代码:

@interface MyClass : NSObject {
    __strong id * myArray; //private byte[] myArray;  <- Java code
}
@property   (nonatomic,readwrite) __strong id * myArray;
@end

这是MyClass中的一个方法:

-(int) getArray: (__strong id *) bufferTmp {

    NSString* aString = @"theString";
    int bytes  = aString.length;

    //now I need to fill the passed in array with the chars of the String
    for (int i = 0; i < bytes; i++) {
            char c = [aString characterAtIndex:i];
            ??? bufferTmp[i] = (UInt8)c;   <----- what to write here?
        }
return bytes;
}

这就是我计划调用此方法来填充myBuffer的方法:

UInt8 myBuffer[10000];
[xxx read: myBuffer];       <-      how to do this correctly ?????

这是等效的Java代码:

public int getArray(byte[] bufferTmp) {
    String theString = "theString";
    for (int i = 0; i < bytes; i++) {
        char c = theString.charAt(i);
        bufferTmp[i] = (byte) c;
        }
     return bytes;

 }

这就是我在Java中调用这个方法的方法:

 byte[] myBuffer = new byte[10000]; 
 int n = read(myBuffer);

1 个答案:

答案 0 :(得分:2)

在Objective-C中,您可以使用NSData个对象作为字节缓冲区,使用dataUsingEncoding来获取字符串的字节表示形式:

NSString *aString = @"theString";
NSData *myBuffer = [aString dataUsingEncoding:NSUTF8StringEncoding];

const char *bytes = [myBuffer bytes]; // pointer to the bytes in the buffer
NSUInteger count = [myBuffer length]; // number of bytes in the buffer