Use c++ to obtain the information of the audio file to achieve the effect of asynchronous playback (2)

Then yesterday's broadcast said

Yesterday's playback can only be accurate to the second level. After testing, I found that it needs to be accurate to the level of milliseconds (at least 100 milliseconds) so that people can't hear any problems.

So I researched and found that I can use the file size / bit rate * 8 to get a more accurate playback time (my own demand is to control it to 100ms)

int bps = 0, timeLength;
float size = 0.0, fBase = 0.1;
int base = 1, index = 0;

string bpsValue = ptrFolder->GetDetailsOf(_variant_t((IDispatch *)ptrItem), 28);
string fileSize = ptrFolder->GetDetailsOf(_variant_t((IDispatch *)ptrItem), 1);

for (int i = bpsValue.size() - 1; i >= 0; i--)
{
char bpsChar = bpsValue[i];
if (bpsChar >= '0' && '9' >= bpsChar)
{
bps = bps + (bpsChar - '0') * base;
base *= 10;
}

}
base = 1;
//Calculate decimals first and then integers
//In the case of decimals
index = fileSize.find_first_of('.');
if (index != -1)
{
for (int i = index + 1; i < fileSize.size(); i++)
{
char sizeChar = fileSize[i];
if (sizeChar >= '0' && '9' >= sizeChar)
{
size = size + (sizeChar - '0') * fBase;
fBase *= 0.1;
}
}
}
else
{
index = fileSize.size();
}
for (int i = index - 1; i >= 0; i--)
{
char sizeChar = fileSize[i];
if (sizeChar >= '0' && '9' >= sizeChar)
{
size = size + (sizeChar - '0') * base;
base *= 10;
}
}


//Accuracy in 100MS units
timeLength = size / bps * 8 * 10;
timeLength = timeLength * 100;

Write very casually, please advise