Convert JSON String to DataTable in ASP.Net

1. using System;
2. using System.Collections.Generic;
3. using System.Data;
4. using System.Text.RegularExpressions;
5. 
   
6. public class ConvertJsonStringToDataTable
7. {
8.    public DataTable JsonStringToDataTable(string jsonString)
9.    {
10.       DataTable dt = new DataTable();
11.       string[] jsonStringArray = Regex.Split(jsonString.Replace("[", "").Replace("]",""), "},{");
12.       List<string> ColumnsName = new List<string>();
13.       foreach (string jSA in jsonStringArray)
14.       {
15.          string[] jsonStringData = Regex.Split(jSA.Replace("{", "").Replace("}", ""),",");
16.          foreach (string ColumnsNameData in jsonStringData)
17.          {
18.             try
19.             {
20.                int idx = ColumnsNameData.IndexOf(":");
21.                string ColumnsNameString = ColumnsNameData.Substring(0, idx - 1).Replace("\"", "");
22.                if (!ColumnsName.Contains(ColumnsNameString))
23.                {
24.                   ColumnsName.Add(ColumnsNameString);
25.                }
26.             }
27.             catch (Exception ex)
28.             {
29.                throw new Exception(string.Format("Error Parsing Column Name : {0}", ColumnsNameData));
30.             }
31.          }
32.          break;
33.       }
34.       foreach (string AddColumnName in ColumnsName)
35.       {
36.          dt.Columns.Add(AddColumnName);
37.       }
38.       foreach (string jSA in jsonStringArray)
39.       {
40.          string[] RowData = Regex.Split(jSA.Replace("{", "").Replace("}", ""), ",");
41.          DataRow nr = dt.NewRow();
42.          foreach (string rowData in RowData)
43.          {
44.             try
45.             {
46.                int idx = rowData.IndexOf(":");
47.                string RowColumns = rowData.Substring(0, idx - 1).Replace("\"", "");
48.                string RowDataString = rowData.Substring(idx + 1).Replace("\"", "");
49.                nr[RowColumns] = RowDataString;
50.             }
51.             catch (Exception ex)
52.             {
53.                continue;
54.             }
55.          }
56.          dt.Rows.Add(nr);
57.       }
58.       return dt;
59.    }
60. }

Resetting IDENTITY Seed in Table Variable

For a "normal" table, you would use: DBCC CHECKIDENT('[table_name]', RESEED, [new_reseed_value]).
you cannot reseed a table variable

A workaround might be to use ROW_NUMBER() instead.

declare @a table (sno int identity,aa nvarchar(100))
insert into @a(aa) values ('testw'),('testwsfsf')

select row_number() OVER (ORDER BY sno) as sno,aa from @a

delete from @a
  
insert into @a(aa) values ('testw'),('testwsfsf')
select row_number() OVER (ORDER BY sno) as sno,aa from @a

How to select alternate rows from a table in SQL Server

Alternate rows from a table:

CREATE TABLE STUDENTS(

      STUDENT_ID int NULL,

      [STUDENT_NAME] [varchar](50) NULL,

      DOB date NULL,

      DEPARTMENT_ID int NULL,

      DOJ date NULL

      )

GO   

INSERT STUDENTS (STUDENT_ID, STUDENT_NAME, DOB, DEPARTMENT_ID,DOJ) VALUES (1, N'ASHISH', '1990-10-28', 2, GETDATE())

INSERT STUDENTS (STUDENT_ID, STUDENT_NAME, DOB, DEPARTMENT_ID,DOJ) VALUES (2, N'MANISH', '1991-06-17', 1, GETDATE())

INSERT STUDENTS (STUDENT_ID, STUDENT_NAME, DOB, DEPARTMENT_ID,DOJ) VALUES (3, N'AMIT', '1992-06-30', 3, GETDATE())

INSERT STUDENTS (STUDENT_ID, STUDENT_NAME, DOB, DEPARTMENT_ID,DOJ) VALUES (4, N'PANKAJ', '1995-10-05', 4, GETDATE())

INSERT STUDENTS (STUDENT_ID, STUDENT_NAME, DOB, DEPARTMENT_ID,DOJ) VALUES (5, N'SUMIT', '1998-04-06', 5, GETDATE())

Method 1:

SELECT STUDENT_ID,STUDENT_NAME,DOB,DEPARTMENT_ID,DOJ FROM(

SELECT ROW_NUMBER()OVER (ORDER BY STUDENT_ID)AS ROW,* FROM STUDENTS)

A WHERE ROW%2=0

Method 2:

WITH CTE AS

(

SELECT ROW_NUMBER()OVER (ORDER BY STUDENT_ID)AS ROW,* FROM STUDENTS

)

SELECT STUDENT_ID,STUDENT_NAME,DOB,DEPARTMENT_ID,DOJ FROM CTE WHERE ROW%2=0

Method 3:

SELECT  ROW_NUMBER()OVER (ORDER BY STUDENT_ID)AS ROW,* INTO_TEMP_STUDENTS FROM  STUDENTS

SELECT STUDENT_ID,STUDENT_NAME,DOB,DEPARTMENT_ID,DOJ FROM_TEMP_STUDENTS WHERE  ROW%2=0

Method 4:

 SELECT IDENT=IDENTITY(int, 1,1),* into TEMP_STUDENTS  FROM STUDENTS

 SELECT STUDENT_ID,STUDENT_NAME,DOB,DEPARTMENT_ID,DOJ FROM TEMP_STUDENTS         WHERE IDENT%2=0