Question

case 3:
 int intAddOption;
 int intOption1;
 Console.WriteLine("Select You Want to Update single Data or Existing Student Record:\n");
 Console.WriteLine("Select 11. for Update single Data ");
 Console.WriteLine("Select 12. For Update Existing Student Record\n");

 intAddOption = Convert.ToInt32(Console.ReadLine());
 if (intAddOption == 11) {

  Console.WriteLine("select which details you want to update:");
  Console.WriteLine("select 1. update Id");
  Console.WriteLine("select 2. update Name");
  Console.WriteLine("select 3. update Contact");
  Console.WriteLine("select update option");
  intOption1 = Convert.ToInt32(Console.ReadLine());

  if (intOption1 == 1) {

   Console.WriteLine("enter Student Id");
   string stringname3 = Console.ReadLine();
   DataRow[] rows = objdatatable.Select("[Student ID] =" + stringname3);
   if (rows != null && rows.Length > 0) {
    foreach(DataRow row in rows) {
     Console.WriteLine("enter Id to update :");
     row["student Id"] = Console.ReadLine();
    }
    Console.WriteLine("number of columns \n{0}", objdatatable.Columns.Count.ToString());
    Console.WriteLine("number of rows \n{0}", objdatatable.Rows.Count.ToString());
    Console.WriteLine("The Deatils Has been update");
    Console.WriteLine("The Total Number of Records \n{0}", objdatatable.Rows.Count.ToString());
   }
  } else if (intOption1 == 2) {
   Console.WriteLine("enter Student Name");
   string stringname4 = Console.ReadLine();
   DataRow[] rows = objdatatable.Select("[student Name] =" + stringname4);
   if (rows != null && rows.Length > 1) {
    foreach(DataRow row in rows) {
     Console.WriteLine("enter Name to update :");
     row["student Name"] = Console.ReadLine();
    }
    Console.WriteLine("number of columns \n{0}", objdatatable.Columns.Count.ToString());
    Console.WriteLine("number of rows \n{0}", objdatatable.Rows.Count.ToString());
    Console.WriteLine("The Deatils Has been update");
    Console.WriteLine("The Total Number of Records \n{0}", objdatatable.Rows.Count.ToString());

   }

  } else if (intOption1 == 3) {
   Console.WriteLine("enter Student Phone No");
   string stringname5 = Console.ReadLine();
   DataRow[] rows = objdatatable.Select("[Student Phone No] =" + stringname5);
   if (rows != null && rows.Length > 0) {
    foreach(DataRow row in rows) {
     Console.WriteLine("enter Student Phone No to update :");
     row["student Phone No"] = Console.ReadLine();
    }
    Console.WriteLine("number of columns \n{0}", objdatatable.Columns.Count.ToString());
    Console.WriteLine("number of rows \n{0}", objdatatable.Rows.Count.ToString());
   }
  }
 }
 if (intAddOption == 12) {
  Console.WriteLine("\nHow Many Record You Want To Add:");
  intcount1 = Convert.ToInt32(Console.ReadLine());
  for (intcount = 1; intcount <= intcount1; intcount++) {
   objdatarow = objdatatable.NewRow();
   Console.WriteLine("\nEnter Student Id:\n");
   objdatarow["student Id"] = Console.ReadLine();
   Console.WriteLine("\nEnter Student Name:\n");
   objdatarow["student Name"] = Console.ReadLine();
   Console.WriteLine("\nEnter student Contact Number:\n");
   objdatarow["phone no"] = Console.ReadLine();
   objdatatable.Rows.Add(objdatarow);
   Console.WriteLine("Again you want to do operation select option:");
   Console.WriteLine("The Deatils Has been updated");
   Console.WriteLine("The Total Number of Records \n{0}", objdatatable.Rows.Count.ToString());
  }
 }


 break;

这里我想更新我的名字栏，但我不能，但学生ID正确更新，学生姓名不能正常工作。

Answer 1

你在这里弄错了。添加引号。

  DataRow[] rows = objdatatable.Select("[student Name] ='" + stringname4 + "'");

基本上它试图将stringname4视为列名而不是字符串。

找不到专栏

1 个答案: