图书借阅管理中的问题

[noreenxqc111]

如图我想根据图书名称中的内容搜索相对应Booklist表中的Book_Borrow的数据并加1，下面的代码，哪里有问题啊,应该怎么改啊




string str = "Data Source=LENOVO-PC\\MRWWK;Initial Catalog=Book;Persist Security Info=True;User ID=sa;Password=123456";
SqlConnection myConn = new SqlConnection(str);
myConn.Open();

string sqlStr = " insert into Bookborrow(Reader_Id,Reader_Name,Book_Name) values('" + txtReaderId.Text + "','" + txtReaderName.Text + "','" + txtBook.Text + "') ";
SqlCommand myCmd = new SqlCommand(sqlStr, myConn);
myCmd.ExecuteNonQuery();

string sqlStr1 = "select Book_Borrow from Booklist where Book_Id='" + txtBook.Text + "'";
SqlCommand select = new SqlCommand(sqlStr1, myConn);
select.ExecuteNonQuery();
string updateSql = "update Booklist set Book_Borrow=Book_Borrow+1 where Book_Id='" + txtBook + "'";
SqlCommand update = new SqlCommand(updateSql, myConn);
update.ExecuteNonQuery();
myConn.Close();

[php_wsd]

Book_Borrow为字符型字段，不能直接+1，改成数字型字段吧