Question

My program throws a System.FormatException: "The entrystring has the wrong format." whenever I am trying run this code:

public double[] ReturnCoordsFromString(string CoordString)
    {
        string[] cArrStr = CoordString.Split(' ');

        List<double> NumList = new List<double>();

        foreach (string elem in cArrStr)
        {
            Console.WriteLine(elem);
            double b = Convert.ToDouble(elem);   // <= Error is here
            NumList.Add(b);
        }
        double[] retN = NumList.ToArray<double>();

        return retN;
    }

I have also tried to run it with Convert.ToDouble(elem) and Encodings with ascii and utf_8. None of these worked.

To understand my code:

I call the function from another function and the CoordString argument looks like this: 90 10 1000 So they are all Integers, but I need them as double. (I tried Int32.Parse() and then convert to double, here it crashes on the Int32.Parse() part)

My code should get the CoordString ("90 10 1000") and split it into single strings (["90", "10", "1000"]). The Console.WriteLine(elem) prints the correct numbers, no letters, just numbers as string.

Any idea why / how to fix it? Nothing other questions suggested worked so far.

EDIT:

The weird thing is, printing elem does work well. But the Exception Window shows me this:

b        0         double
elem     ""        string
// The class name here

Answer 1

你可能在某个地方有一个双重空间导致了这个问题。尝试指定StringSplitOptions.RemoveEmptyEntries：

string[] cArrStr = CoordString(' ', StringSplitOptions.RemoveEmptyEntries)

而不是

string[] cArrStr = CoordString.Split(' ');

此外，您应该使用Double.TryParse而不是Convert.ToDouble，因为Double.TryParse只会在无法转换时返回false，而Convert.ToDouble会抛出异常：

所以使用这个：

double b;
if(Double.TryParse(elem, out d))
{
    // value is a double
}

而不是

double b = Convert.ToDouble(elem);

System.Format.FormatException when trying double.Parse()

1 个答案: