How to iterate through two dimensional array

I have two list that I convert them to a single two dimesnional array like this:

double[,] data = new double[voltage.Count(), 2];
for (int i = 0; i < voltage.Count(); i++)
{
    data[i, 0] = voltage[i];
    data[i, 1] = current[i];
}

Now I am trying to itterate through this array but what I get is same value for both voltage and current in each line:

foreach (double data in ztr.GetCurveDataForTestType()) //this will return my array
{
    richTextBox1.AppendText("Voltage" + data + "    ---------    ");
    richTextBox1.AppendText("Current" + data + "\r\n");
}

Voltage-0.175 --------- Current-0.175

Voltage-9.930625E-06 --------- Current-9.930625E-06

Voltage-0.171875 --------- Current-0.171875

Voltage-9.53375E-06 --------- Current-9.53375E-06

Voltage-0.16875 --------- Current-0.16875

As you see in the first line both voltage and开发者_开发技巧 current are same value that is voltage, and on the second raw they are the same again but this time it is the current value. How can I fix this?

I'd recommend not using multi-dimensional arrays for this.

Instead you can make a class something like this:

class Measurement
{
    public double Voltage { get; set; }
    public double Current { get; set; }
}

And change your method to return IEnumerable<Measurement>. In .NET 4.0 you can use Zip:

public IEnumerable<Measurement> GetCurveDataForTestType()
{
    return voltage.Zip(current,
        (v, c) => new Measurement { Voltage = v, Current = c});
}

And for older versions of .NET:

public IEnumerable<Measurement> GetCurveDataForTestType()
{
    for (int i = 0; i < voltage.Count(); i++)
    {
        yield return new Measurement
        {
            Voltage = voltage[i],
            Current = current[i]
        };
    }
}

Then your code becomes:

foreach (Measurement data in ztr.GetCurveDataForTestType())
{
    richTextBox1.AppendText(
        "Voltage: {0} ---------  Current: {1}", data.Voltage, data.Current);
}

You use the same kind of loop as when you created the array:

for (int i = 0; i < data.GetLength(0); i++) {
  richTextBox1.AppendText("Voltage" + data[i, 0] + "    ---------    ");
  richTextBox1.AppendText("Current" + data[i, 1] + "\r\n");
}

Update: This question appears to be a duplicate of How to foreach through a 2 dimensional array?. The linked answer has an alternate solution that enables the use of foreach by switching from a two-dimensional array to an array of array.

foreach with a two dimensional array, will sequentially return every double value in the array (by design).

For example, given the following two-dimensional array of doubles:

var array = new double[,] { { 0, 1, }, { 2, 3 }, { 4, 5 } };

foreach (var d in array)
{
    Console.WriteLine(d);
}

You will get the following Console output:

0
1
2
3
4
5

Therefore, foreach is not appropriate for you needs. You should use a for loop.