converting to double to two decimal places

Question

Hi i am a c# novice would someone politely tell me how to convert the values of this piece of code to a double/rounded decimal.. thanks in advance

DataTable dtValues = new DataTable("GetValues");

strValueNumber = ValueNumber[0].ToString();
dtGetValues = SQLMethods.GetValues(strValueNumber);

total = 0;

for (int i = 0; i < dtValues.Rows.Count; i++)
{
    total1 = total1 + Convert.ToInt32(dtGetValues.Rows[i]["total_1"]);                  
    total2 = total2 + Convert.ToDouble(dtGetValues.Rows[i]["total_2l"]) * .45; 

    tbtotal1.Text = total1.ToString();
    tbtotal2.Text = total2.ToString(); 
}
}               
catch (Exception ex)
{
    MessageBox.Show("Error in returning selected Values. " +
                    "Processed with error:" + ex.Message);
}
}

Solution 1

Use Math.Round

Math.Round(mydoublevalue, 2);

In your code

tbtotal2.Text = Math.Round(total2, 2).ToString(); 

Solution 2

My answer is pretty late but for those out there like me who want:

to convert to double/decimal and also want the value to always show 2 decimal places (.00) as String

tbtotal2.Text = Math.Round(total2, 2).ToString("#.00"); 

The below means two decimal places at all times.

"#.00"

The below means two decimal places if there is value.

"#.##"

Solution 3

If you only want the value rounded for display as a string, you can also use String.Format.

tbtotal1.Text = String.Format("{0:0.##}", total1);

The text "{0:0.##}" describes how you want it to be formatted. The # indicates that ending zeroes should not be included (eg 1.2 stays the string "1.2"), if you instead do "{0:0.00}", two decimal places are included no matter what, so the double 1.2 would become "1.20".

Solution 4

Do it like this.

 tbtotal1.Text = Math.Round(double.Parse(total1.ToString()), 2).ToString();
 tbtotal2.Text = Math.Round(double.Parse(total2.ToString()), 2).ToString(); 

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