今天想用參數化SQL語句進行模糊查找,一開始的使用方法不正確,摸索了好一會。
1、使用參數化SQL語句進行模糊查找的正確方法:
//定義sql語句
string sql = "SELECT StudentID,StudentNO,StudentName FROM Student WHERE StudentName like @StudentName";
//給參數賦值
command.Parameters.AddWithValue("@StudentName", "%"+txtStudentName.Text+"%");
2、錯誤做法1:
//定義sql語句
string sql = "SELECT StudentID,StudentNO,StudentName FROM Student WHERE StudentName like @StudentName";
//給參數賦值
command.Parameters.AddWithValue("@StudentName", "'%"+txtStudentName.Text+"%'");
3.錯誤做法2:
//定義sql語句
string sql = "SELECT StudentID,StudentNO,StudentName FROM Student WHERE StudentName like '@StudentName%'";
//給參數賦值
command.Parameters.AddWithValue("@StudentName", txtStudentName.Text);
4.錯誤做法3:
//定義sql語句
string sql = "SELECT StudentID,StudentNO,StudentName FROM Student WHERE StudentName like @StudentName%";
//給參數賦值
command.Parameters.AddWithValue("@StudentName", txtStudentName.Text);