What is the best approach to Convert DataTable into .CSV

Question

I have written the following two approach to Convert DataTable into .csv File

 

First Approach 

 

Step 1: 

By iteratiing over DataTable put all Coulmns then after each rows column's data with comma (,) separated into a StringBuilder object

 

Step 2: 

 

Now create a new File1.csv file with StringBuilder object which contains csv file data. 

 

Second Approach

Step 1: 

Now create a new File1.csv file with empty string data.

Step 2:

Now use the file path of File1.csv to create a StreamWriter object (ie. sw) and use sw.Write() method into loop to of DataTable Rows.

Using StringBuilder or StreamWriter, which one is best.

 

If any other may be a best approach, kindly share.