For 循环只显示最后一个循环 C#

Question

How can I get the results to show each year and the year end value for each year?

double investment_decimal = Double.Parse(txtAmount.Text);
double rate_decimal = Double.Parse(txtRate.Text);
double years = Double.Parse(txtSlideValue.Text);
years = Convert.ToDouble(txtSlideValue.Text);
double calculation = 0;

        //for loop
            for (int i = 1; i < years + 1 ; i++)
            {

                calculation = investment_decimal * Math.Pow((1 + rate_decimal / years), (i));
                txtCalculation.Text = Convert.ToString("Year " + i.ToString() +"\t" + "Year End Value " + calculation.ToString("C")).PadRight(10);
            }

Answer 1

Your code makes multiple assignments to a UI element's text before letting UI refresh. That is why only the last item remains visible; the rest of them get overwritten as you go through the loop.

You should prepare a string that corresponds to the entire string in the text box, and put it into txtCalculation.Text all at once:

StringBuilder sb = new StringBuilder();
for (int i = 1; i < years + 1 ; i++)
{

    calculation = investment_decimal * Math.Pow((1 + rate_decimal / years), (i));
    sb.AppendFormat("Year {0}\tYear End Value {1:C}\n", i, calculation);
}
txtCalculation.Text = sb.ToString();

Note the use of AppendFormat in place of string concatenation operator += with multiple values. If you want to make a string, rather than appending to StringBuffer , you could use string.Format or interpolated strings of C# 6.