how to convert empty string to double

Question

double mrp = Convert.ToDouble(gvRow.Cells[9].Text.ToString());

In the above code when mrp = "6458.0" it works fine but somtimes when mrp is empty now it throws an exception.kindly help me to solve this issue....

Answer 1

Use Double.TryParse, this will not throw an exception and if the parsing fails then you will get 0 as the parsed value.

double number;
if (double.TryParse(gvRow.Cells[9].Text, out number))
{
    //valid
}
{
    //invalid
}

//if invalid then number will hold `0`

Answer 2

Use Double.TryParse to check if the conversion succeeds or not.

double mrp;
if (Double.TryParse(gvRow.Cells[9].Text.ToString(), out mrp))
{
   // Success
}
else
{
  // Cannot convert to double
}

Also, You might want to use Double.IsNan

Answer 3

you should try this: double mrp = gvRow.Cells[9].Text.ToString() != "" ? Convert.ToDouble(gvRow.Cells[9].Text.ToString()): 0.0;

Answer 4

if (Double.TryParse(gvRow.Cells[9].Text.ToString(), out mrp))
   Console.WriteLine("Ok");
else
   Console.WriteLine("not a number");

Answer 5

You can use double.Tryparse..

 double num; 

if(Double.Tryparse(gvRow.Cells[9].Text.ToString(),num) 
{
  // get the converted value
}
else
{
  //invalid
}

Answer 6

You should use Double.TryParse as others talked about.

But as an alternative way, you can validate your cells by data type checking, or it shouldn't be null etc.

Answer 7

Try double.tryParse

Reference

Convert.ToDouble will throw an exception on non-numbers
Double.Parse will throw an exception on non-numbers or null
Double.TryParse will return false or 0 on any of the above without generating an exception.