How to fix the error - Unable to cast object of type 'System.Int32' to type 'System.String'

Question

Dear All,

How to fix the error - Unable to cast object of type 'System.Int32' to type 'System.String'

Answer 1

Hi @BenTam-3003 , Welcome to Microsoft Q&A,

Because the StudentID you selected is int32.

Try using tostring() to convert it to string first.

string tmp = string.Format("{0}", row.Field<int>("StudentID").ToString());

In this code, I've replaced row.Field<string>("StudentID") with row.Field<int>("StudentID").ToString() to explicitly convert the integer value to a string before using it in the string.Format method. This should resolve the casting issue.

Best Regards,

Jiale

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