Convert from float to QByteArray

Is there a quick way to convert a float value to a byte wise (hex) representation in a `QByteArray`?

Have done similar with `memcpy()` before using arrays, but this doesn't seem to work too well with `QByteArray`.

For example:

memcpy(&byteArrayData,&floatData,sizeof(float));

Can go the other way just fine using:

float *value= (float *)byteArrayData.data();


Am I just implementing this wrong or is there a better way to do it using Qt?

Thanks

I'm not sure what you want exactly.

To stuff the binary representation into a QByteArray you can use this:

float f = 0.0f;
QByteArray ba(reinterpret_cast<const char *>(&f), sizeof (f));

To get a hex representation of the float you can add this:

QByteArray baHex = ba.toHex();

From the [QByteArray Class Reference][1] page:

float f = 0.0f;
QByteArray array(reinterpret_cast<const char*>(&f), sizeof(f));


Will initialize a `QByteArray` with the memory content of the float stored in it.

If you already have one and just want to append the data to it:

array.append(reinterpret_cast<const char*>(&f), sizeof(f));

Should do it as well.

To go the other way around, you just have to perform the reverse operation:

float f2;

if (array.size() >= sizeof(f2)
{
f2 = *reinterpret_cast<const float*>(array.data());
} else
{
// The array is not big enough.
}


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