to type double is not valid

Hi,
 Iam getting an Exception in Code"to type double is not valid"
Iam having an SQL Query in my Code which finds the difference between two values and returns its Absolute value.

Code Snippet

1 2 Dim originalprice as String =array(1).Trim.ToString 3 4 Dim p1 As Double = Convert.ToDouble(originalprice) 5 6 Select * from table where abs(price1 -p1) < 20Please Suggest a SolutionThanks in advance  
  

 
 
 

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