.NET trouble when using doubles

In .NET, when I subtract 1.35 from 1.35072 it shows .000719999999. How could I get .00072 when using a double?

TOTKILO.Text = KILO.Text * TOUCH.Text * 0.01;    //here 1.35072
TextBox10.Text = TextBox9.Text * TextBox8.Text * 0.01; //here 1.35
K = Val(TOTKILO.Text) - Val(TextBox10.Text);  开发者_如何学运维//here it shows 0.00719999

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Depends on what you're really asking.

If you want to round to five decimal places, you can just do:

double x = 1.35072;
double y = 1.35;
double z = Math.Round(x - y, 5); // 0.00072

If, on the other hand, your goal is to always get precise results from adding/subtracting decimal numbers, use the decimal type instead of double since it is inherently a base-10 type (as opposed to a base-2 type) and can therefore represent numbers expressed in decimal form precisely.

decimal x = 1.35072M;
decimal y = 1.35M;
decimal z = x - y; // 0.00072M

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From what I've seen, you almost never actually need a double. Nearly all the time a decimal (System.Decimal) works for what you need, and it is an exact number, not a floating point representation, so you'll never have these rounding problems.

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Doubles and floating points are always represented with a varying degree of precision than what we visualize them to be. Always round up the values to few decimals and then check the answers.

Additional details are in How To Work Around Floating-Point Accuracy/Comparison Problems.