how to find the total sum of particular column using C# ?
Suppose In database their is column called INCOME_PER_DAY. I bring data of this column in the gridview .

Now  My question is that I want to find the total sum of the column INCOME_PER_DAY using C# .how to do this? 

Please tell me. 
how to find the total sum of particular column using C# ?
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Suppose In database their is column called INCOME_PER_DAY. I bring data of this column in the gridview .

Now  My question is that I want to find the total sum of the column INCOME_PER_DAY using C# .how to do this? 

Please tell me. 