public void ChangeTexts(long length, int position, int percent, double speed)
{
Label3.Text = "File Size: " + Math.Round((length / 1024), 2) + " KB";
Severity Code Description Project File Line Suppression State Error CS0121 The call is ambiguous between the following methods or properties: 'Math.Round(double, int)' and 'Math.Round(decimal, int)'
You're currently dividing by 1024 in integer arithmetic and then rounding the result. In other words, you're rounding something that's already an integer - not really useful.
The simplest fix is to divide by 1024.0 instead, to make it happen in double
arithmetic:
Label3.Text = "File Size: " + Math.Round((length / 1024.0), 2) + " KB";
Or better, just do it within the formatting itself:
Label3.Text = $"File Size: {length / 1024.0:0.00}KB";
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