ERP Development using c# - SQL Server

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Chapter : 1. Introduction.

The .Net Framework 3.5
Create an ASP.Net 3.5 application
Code models in ASP.Net 3.5
Single-File Page Model
Code behind Page model
Which model is better?
Advantages of Single-File Pages
Advantages of Code-Behind Pages
ASP.NET Page Syntax
Overview of ASP.Net server controls
Standard Controls
Data Controls
Validation Controls
Navigation Controls
Login Controls
HTML Controls
ASP.NET AJAX Extensions Controls
WebParts
How to wire multiple controls in a page to the same event handler
Using ListBoxes and DropDown Lists
Creating Multiple-Selection List boxes
Get the selected Item in the single-selection ListBox control
Get the selected Items in the multiple-selection ListBox control
SelectedIndexChanged event of ListBox control
Creating ListItem objects and adding them to a Control using the Add() method
Removing Items from a specific location
Removing Items from a multiple-selection ListBox control
Using CheckBoxes and RadioButtons
Get the Selected Item in a RadioButton Control using Radio button click event
Check Box control
RadioButtonList and CheckBoxList controls
Get selected items from the CheckBoxList control
Validation Controls
RequiredField Validator
ErrorMessage Property
Using InitialValue property of RequiredFieldValidator with TextBox control
Using InitialValue property of RequiredFieldValidator with DropDownList control
Display Property
Enabled Property
EnableClientScript Property
The CompareValidator Control
Performing a Data type Check
RangeValidator Control
Regular Expression Validator Control
CustomValidator Control
Client-Side Validation
ValidationSummary Control
Using Validation Groups
How to use a single button to validate multiple validation groups
Chapter : 2. Data Access in ASP.Net 3.5.
The SqlDataSource control
How to Connect to a SQL Server Database Using the SqlDataSource Control
Creating a SqlDataSource control declaratively
Storing Connection String in Web.config file
Executing Data Commands with the SqlDataSource Control
Binding a ListBox Control to the SqlDataSource control
Setting DataSouceMode property
SqlDataSource control Events
Using parameters with SqlDataSource control
Properties of ASP.Net parameter objects
SqlDataSource control Collections
How to set SqlDataSource's parameters before the select command is executed
Using the ASP.Net ControlParameter Object
Overview of GridView control
Properties of GridView control
GridView Events
GridView Methods
Display, edit and delete data in the GridView control using SqlDataSource control
Programmatic DataBinding in a GridView Control
Formatting GridView control
Formatting GridView control with CSS
Using fields with the GridView control
Using BoundFields
How to Format date and currency column using DataFormatString property
Using Command Fields
Using Template Fields
How to use Eval() and Bind() method
Display a DropDownList when Editing in the GridView using EditItemTemplate
How to insert new data into the database with GridView control using FooterTemplate
How to restrict an item from being selected using GridView SelectedIndexChanging Event
DetailsView and FormView control
Using Fields in a DetailsView control
Using style elements in a DetailsView control
Creating a DetailsView control
Data Binding with the DetailsView Control
Using DataSourceID property
Using DataSource property
DetailsView Properties
DetailsView Events
Using Command buttons in DetailsView
Using Templates in a DetailsView control
How to create Master - Detail page by using GridView and DetailsView control
FormView control
FormView vs. DetailsView control
How to use FormView control to update and insert data
Chapter : 3. ERP Application Architecture
Benefits of Multi-tier Architecture
Purpose of Presentation Layer
Purpose of Business Layer
Purpose of Data Access Layer
Purpose of Data Layer
Creating Web ERP Application Framework using Visual Studio
Creating a Class Library for the Data Access Layer
Creating a Class Library for the Business Layer
Creating a Web Application for the Presentation Layer
Developing Data Access Layer in C#
Creating DataServer Class
Constructor of the DataServer class
DataServer Class Methods
Introduction to Master pages
Creating a Master page for the ERP Web Application
How to place a Menu control on a Master page
Chapter : 4. Developing Finance Module
Business processes in Finance Module
Presentation Layer of Finance Module
Creation of Accounts
Designing and Programming the AccountsDialog.aspx
Managing ASP.Net Navigation using Server.Transfer method
Send a parameter to another page using Server.Transfer method
Designing and Programming the AccountsForm.aspx
Bind the DropDownList control to a ObjectDataSource control
Using SelectMethod property of ObjectDataSource
TypeName property of ObjectDataSource
OnSelecting property of ObjectDataSource
Import the namespace of Business Layer
Retrieve Query String Values in Page_Load() event using Request.QueryString
Set ObjectDataSource's parameters using Selecting event - ObjectDataSource1_Selecting
Save the Account Details
Creating Business Object - Account.cs
Retrieve Groups
Steps to interact with the DataAccessLayer
Save the Account details
Connecting AccountForm to the menu
Creating Customer, Supplier, Bank and General Account using the AccountsForm.aspx
Chart of Accounts
Designing and Programming Chart of Accounts.aspx
Placing a TreeView control on a ChartofAccounts.aspx
Populate the root level nodes in Page_Load() event
Populate the child nodes of a given node
Program the TreeNodePopulate event
Creating Business Object - Group.cs
Return main groups
Return only sub-groups under a particular group
Designing the JournalForm.aspx for the Journal Voucher Transaction
Steps to design the JournalForm.aspx
Create and set important properties and methods of the GridView control
Create Template columns in the GridView control using asp:TemplateField element
ItemTemplate
EditItemTemplate
Footer Template
Create a Template column for the AccountName column in the JV
Create a Template column for the Debit column in the JV
Create a Template column for the Credit column in the JV
Create a Template column for 'Insert' Button
Create a 'Delete' Command button and 'Edit' Command button
Create EmptyDataTemplate to accept first row of data when datasource is empty
How to place the ObjectDatasource control, Transaction number, Date and totals of Credit and Debit column amounts on the form
How to insert multiple accounts in the GridView control
Steps to program the JournalForm.cs
Building the DataTable Structure for the GridView
Program the Page_Load event to bind the DataTable to the GridView control
Program the Add New Record button to add a new row of data to the GridView using EmptyDataTemplate
Access the controls placed in the EmptyDataTemplate
Program the Insert button to add a new row of data to the GridView using FooterTemplate
Retrieve the values of controls (DropDownList and TextBox controls) which are in the Footer Template
Retrieve existing accounts from the Session object and assign to DataTable
Save the DataTable into a session
To get the value from a particular cell, which is a TemplateField
Program the Event handler for the EditCommand event
protected void grdAccounts_RowEditing(object sender, GridViewEditEventArgs e)
Program the Cancel button
protected void grdAccounts_RowCancelingEdit(Object sender, GridViewCancelEditEventArgs e)
Program the Event handler for the DeleteCommand event
protected void grdAccounts_RowDeleting(object sender, GridViewDeleteEventArgs e)
Delete a row from the DataTable
Commit all the changes made to this DataTable
Assign DataTable as DataSource to the GridView and bind the GridView
To clear the selection of a row, we set the SelectedIndex property programmatically to -1
Program the Update button
protected void grdAccounts_RowUpdating(object sender,GridViewUpdateEventArgs e)
Program the function which keeps a running total of the debit amounts of the accounts
Program the procedure for checking Double Entry rule
Program the Save button
Designing and Programming Voucher/ Receipts Transactions
Cash Voucher
Cash Receipt
Check Voucher
Check Receipt
Creating Business Object - Transaction.cs
Return Cash and Bank Accounts
Return Accounts based on menu selection
Save transaction details and return boolean value if transaction updation is successful
Chapter : 5. Developing Sales and Purchase Module
Business processes in Sales Module
Design and Program the OrderForm.aspx for creating Sales orders and purchase orders
Place the DropDownList control and bind it to the ObjectDataSource control to display customer names
How to insert multiple items in the orderForm.aspx
Perform Validations in order Form
Save Sales order /Purchase orders
Update Order details
Program the function which calculates the order total
Program the function for calculating order net amount
Designing and Programming ordersGrid.aspx
Pick and Pack Sales orders
Pick Shipping orders
Back orders
Pending Purchase orders
Designing and Programming InvForm.aspx
Program the function which calculates the invoice total
Program the procedure for checking Double Entry rule
Program the Save button
Validate the TextBox control placed in the Footer using TextChanged event
Validate the TextBox control placed in the EmptyDataTemplate using TextChanged event
Programming Purchase Invoice
Programming Sale Invoice
Programming the Cash Sales
Programming the Cash Purchase
Programming Purchase Returns
Programming Sale Returns
Business Object - Trade
Retrieve Customer/Vendor Accounts
Retrieve Trade Accounts from the database
Retrieve Discount, Freight and Tax Accounts
Saving the Transaction details
Chapter : 6. Developing Inventory Module
Business processes in Inventory Module
Designing and programming the ItemForm.aspx for creating different types of items - Raw Material, Consumable, Sub Assembly or a Finished Product
Designing and programming the MaterialIssueForm.aspx to issue components to manufacture products
Business Layer of Inventory Module
Business Object - Item.cs
Retrieve Stock Groups from database
Retrieve Item types
Save the Item details
Business Object - Issue
Return information about single Work order
Saving Issue details
Chapter : 7. Developing the Manufacturing Module
Business processes in Manufacturing Module
Designing and Programming BOMForm.aspx for Creating Bill of Materials
Designing and Programming WorkOrderForm.aspx for creating work orders
Business Layer of Manufacturing Module
Business Objects - BOM
Return information about all Items
Return list of Poducts
Return Components for a parent Item
Save Product Structure
Create product structures using BOMForm.aspx
Display product structures using BOMDisplay.aspx
Business Objects - WorkOrder
Return names of Products
Return Information about Components and their Quantities which are required to manufacture one parent item (product)
Save Work Order details

ERP development is a broad topic which encompasses :
- Business requirements
- Technical requirments
- ...

This is a very hard question to answer in a forum like this. Try asking specific questions next time.