Failed to load resource: the server responded with a status of 404 (File not found) for image

If the image not find set the default image.

Use this:-
onerror="this.onerror=null; this.src='../images/Default.png'"

Example:-

 <img  src="images.png" alt="User Image" onerror="this.onerror=null; this.src='Default.png'" >

Error Logger in .net Core

To configuring Elmah follow the following steps in the Code:

1. Start the NuGet Solution .
2. Download the 2 package Elmahcore, ElmahCore.Sql
    as shown in the image

3. Open the Startup.cs Page

    Add using ElmahCore;

           using ElmahCore.Sql;

    directives in the top of the page.

4. In the ConfigureServices method add the following code.

    

            services.AddElmah<SqlErrorLog>(options =>

            {

                options.ConnectionString = AppSetting.ConnectionString;

            });

5. In the Configure method, add the following code:

app.UseElmah();

In the SQL Execute the following Query:-

1. Create a table to capture the Error

/****** Object: Table [dbo].[ELMAH_Error] Script Date: 9/5/2019 2:49:51 PM ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[ELMAH_Error]( [ErrorId] [uniqueidentifier] NOT NULL, [Application] [nvarchar](60) NOT NULL, [Host] [nvarchar](50) NOT NULL, [Type] [nvarchar](100) NOT NULL, [Source] [nvarchar](60) NOT NULL, [Message] [nvarchar](500) NOT NULL, [User] [nvarchar](50) NOT NULL, [StatusCode] [int] NOT NULL, [TimeUtc] [datetime] NOT NULL, [Sequence] [int] IDENTITY(1,1) NOT NULL, [AllXml] [ntext] NOT NULL, CONSTRAINT [PK_ELMAH_Error] PRIMARY KEY NONCLUSTERED ( [ErrorId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY] GO ALTER TABLE [dbo].[ELMAH_Error] ADD CONSTRAINT [DF_ELMAH_Error_ErrorId] DEFAULT (newid()) FOR [ErrorId] GO /****** Object: StoredProcedure [dbo].[ELMAH_GetErrorsXml] Script Date: 9/5/2019 2:49:53 PM ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO

2. Execute the blow Procedure

CREATE PROCEDURE [dbo].[ELMAH_GetErrorsXml] ( @Application NVARCHAR(60), @PageIndex INT = 0, @PageSize INT = 15, @TotalCount INT OUTPUT ) AS SET NOCOUNT ON DECLARE @FirstTimeUTC DATETIME DECLARE @FirstSequence INT DECLARE @StartRow INT DECLARE @StartRowIndex INT SELECT @TotalCount = COUNT(1) FROM [ELMAH_Error] WHERE [Application] = @Application -- Get the ID of the first error for the requested page SET @StartRowIndex = @PageIndex * @PageSize + 1 IF @StartRowIndex <= @TotalCount BEGIN SET ROWCOUNT @StartRowIndex SELECT @FirstTimeUTC = [TimeUtc], @FirstSequence = [Sequence] FROM [ELMAH_Error] WHERE [Application] = @Application ORDER BY [TimeUtc] DESC, [Sequence] DESC END ELSE BEGIN SET @PageSize = 0 END -- Now set the row count to the requested page size and get -- all records below it for the pertaining application. SET ROWCOUNT @PageSize SELECT errorId = [ErrorId], application = [Application], host = [Host], type = [Type], source = [Source], message = [Message], [user] = [User], statusCode = [StatusCode], time = CONVERT(VARCHAR(50), [TimeUtc], 126) + 'Z' FROM [ELMAH_Error] error WHERE [Application] = @Application AND [TimeUtc] <= @FirstTimeUTC AND [Sequence] <= @FirstSequence ORDER BY [TimeUtc] DESC, [Sequence] DESC FOR XML AUTO

CREATE PROCEDURE [dbo].[ELMAH_GetErrorXml]

(

    @Application NVARCHAR(60),

    @ErrorId UNIQUEIDENTIFIER

)

AS

    SET NOCOUNT ON

    SELECT 

        [AllXml]

    FROM 

        [ELMAH_Error]

    WHERE

        [ErrorId] = @ErrorId

    AND

        [Application] = @Application

CREATE PROCEDURE [dbo].[ELMAH_LogError]

(

    @ErrorId UNIQUEIDENTIFIER,

    @Application NVARCHAR(60),

    @Host NVARCHAR(30),

    @Type NVARCHAR(100),

    @Source NVARCHAR(60),

    @Message NVARCHAR(500),

    @User NVARCHAR(50),

    @AllXml NTEXT,

    @StatusCode INT,

    @TimeUtc DATETIME

)

AS

    SET NOCOUNT ON

    INSERT

    INTO

        [ELMAH_Error]

        (

            [ErrorId],

            [Application],

            [Host],

            [Type],

            [Source],

            [Message],

            [User],

            [AllXml],

            [StatusCode],

            [TimeUtc]

        )

    VALUES

        (

            @ErrorId,

            @Application,

            @Host,

            @Type,

            @Source,

            @Message,

            @User,

            @AllXml,

            @StatusCode,

            @TimeUtc

        )

To check its woking or not create exception use this code:

app.Run(async (context) =>

{ await context.Response.WriteAsync("Hello World!"); int[] numbers = new int[5]; await context.Response.WriteAsync(numbers[6].ToString()); });

Use Query in SQL

SELECT * FROM dbo.ELMAH_Error

Configuring Elmah for use with ASP.NET Core

To configuring Elmah follow the following steps in the Code:

1. Start the NuGet Solution .
2. Download the 2 package Elmahcore, ElmahCore.Sql
    as shown in the image

3. Open the Startup.cs Page

    Add using ElmahCore;

           using ElmahCore.Sql;

    directives in the top of the page.

4. In the ConfigureServices method add the following code.

    

            services.AddElmah<SqlErrorLog>(options =>

            {

                options.ConnectionString = AppSetting.ConnectionString;

            });

5. In the Configure method, add the following code:

app.UseElmah();

In the SQL Execute the following Query:-

1. Create a table to capture the Error

/****** Object: Table [dbo].[ELMAH_Error] Script Date: 9/5/2019 2:49:51 PM ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[ELMAH_Error]( [ErrorId] [uniqueidentifier] NOT NULL, [Application] [nvarchar](60) NOT NULL, [Host] [nvarchar](50) NOT NULL, [Type] [nvarchar](100) NOT NULL, [Source] [nvarchar](60) NOT NULL, [Message] [nvarchar](500) NOT NULL, [User] [nvarchar](50) NOT NULL, [StatusCode] [int] NOT NULL, [TimeUtc] [datetime] NOT NULL, [Sequence] [int] IDENTITY(1,1) NOT NULL, [AllXml] [ntext] NOT NULL, CONSTRAINT [PK_ELMAH_Error] PRIMARY KEY NONCLUSTERED ( [ErrorId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY] GO ALTER TABLE [dbo].[ELMAH_Error] ADD CONSTRAINT [DF_ELMAH_Error_ErrorId] DEFAULT (newid()) FOR [ErrorId] GO /****** Object: StoredProcedure [dbo].[ELMAH_GetErrorsXml] Script Date: 9/5/2019 2:49:53 PM ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO

2. Execute Procedure the blow Procedure

CREATE PROCEDURE [dbo].[ELMAH_GetErrorsXml] ( @Application NVARCHAR(60), @PageIndex INT = 0, @PageSize INT = 15, @TotalCount INT OUTPUT ) AS SET NOCOUNT ON DECLARE @FirstTimeUTC DATETIME DECLARE @FirstSequence INT DECLARE @StartRow INT DECLARE @StartRowIndex INT SELECT @TotalCount = COUNT(1) FROM [ELMAH_Error] WHERE [Application] = @Application -- Get the ID of the first error for the requested page SET @StartRowIndex = @PageIndex * @PageSize + 1 IF @StartRowIndex <= @TotalCount BEGIN SET ROWCOUNT @StartRowIndex SELECT @FirstTimeUTC = [TimeUtc], @FirstSequence = [Sequence] FROM [ELMAH_Error] WHERE [Application] = @Application ORDER BY [TimeUtc] DESC, [Sequence] DESC END ELSE BEGIN SET @PageSize = 0 END -- Now set the row count to the requested page size and get -- all records below it for the pertaining application. SET ROWCOUNT @PageSize SELECT errorId = [ErrorId], application = [Application], host = [Host], type = [Type], source = [Source], message = [Message], [user] = [User], statusCode = [StatusCode], time = CONVERT(VARCHAR(50), [TimeUtc], 126) + 'Z' FROM [ELMAH_Error] error WHERE [Application] = @Application AND [TimeUtc] <= @FirstTimeUTC AND [Sequence] <= @FirstSequence ORDER BY [TimeUtc] DESC, [Sequence] DESC FOR XML AUTO

CREATE PROCEDURE [dbo].[ELMAH_GetErrorXml]

(

    @Application NVARCHAR(60),

    @ErrorId UNIQUEIDENTIFIER

)

AS

    SET NOCOUNT ON

    SELECT 

        [AllXml]

    FROM 

        [ELMAH_Error]

    WHERE

        [ErrorId] = @ErrorId

    AND

        [Application] = @Application

CREATE PROCEDURE [dbo].[ELMAH_LogError]

(

    @ErrorId UNIQUEIDENTIFIER,

    @Application NVARCHAR(60),

    @Host NVARCHAR(30),

    @Type NVARCHAR(100),

    @Source NVARCHAR(60),

    @Message NVARCHAR(500),

    @User NVARCHAR(50),

    @AllXml NTEXT,

    @StatusCode INT,

    @TimeUtc DATETIME

)

AS

    SET NOCOUNT ON

    INSERT

    INTO

        [ELMAH_Error]

        (

            [ErrorId],

            [Application],

            [Host],

            [Type],

            [Source],

            [Message],

            [User],

            [AllXml],

            [StatusCode],

            [TimeUtc]

        )

    VALUES

        (

            @ErrorId,

            @Application,

            @Host,

            @Type,

            @Source,

            @Message,

            @User,

            @AllXml,

            @StatusCode,

            @TimeUtc

        )

To check its woking or not create exception use this code:

app.Run(async (context) =>

{ await context.Response.WriteAsync("Hello World!"); int[] numbers = new int[5]; await context.Response.WriteAsync(numbers[6].ToString()); });

Use Query in SQL

SELECT * FROM dbo.ELMAH_Error

The breakpoint will not currently be hit. No symbols have been loaded for this document

Solution of this error :-

Change the build configuration "Release" to "Debug" Mode.

HttpContext.Current.User.Identity.Name returns null or empty string

This error come due to authentication mode problem.

To correct this  error follow the following step:

1. Select your project.
2. press F4.
3. the screen will open like the below image.
4. disable the "Anonymous Authentication" and enable the "Window Authentication".

paste in the web configuration

<system.web>
    <authentication mode="Windows">
</system.web>

All tables name like

ome time we need to get all the tables which start with any character.We have imported data form excel sheet to MS SQL database. Now want to get list of table and delete the imported data table from database.

This query will helpful to get the table from database

SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES

WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_NAME LIKE '%$%'

Drop all db objects

Some time we need to restore the database with the help of MS SQL server generate script.
We need to flow these Steps

1. Generate Database Scripts(Schema and data)
2. Drop all db objects
3. Restore Generated script   

Drop all db objects

This below script user can use to drop all database objects from database and

1. Store procedures
2. Views
3. Functions
4. Tables

DB Utility script

/* Drop all non-system stored procs */
DECLARE @name VARCHAR(128)
DECLARE @SQL VARCHAR(254)
SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'P' AND category = 0 ORDER BY [name])
WHILE @name is not null
BEGIN
    SELECT @SQL = 'DROP PROCEDURE [dbo].[' + RTRIM(@name) +']'
    EXEC (@SQL)
    PRINT 'Dropped Procedure: ' + @name
    SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'P' AND category = 0 AND [name] > @name ORDER BY [name])
END
GO
/* Drop all views */
DECLARE @name VARCHAR(128)
DECLARE @SQL VARCHAR(254)
SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'V' AND category = 0 ORDER BY [name])
WHILE @name IS NOT NULL
BEGIN
    SELECT @SQL = 'DROP VIEW [dbo].[' + RTRIM(@name) +']'
    EXEC (@SQL)
    PRINT 'Dropped View: ' + @name
    SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'V' AND category = 0 AND [name] > @name ORDER BY [name])
END
GO
/* Drop all functions */
DECLARE @name VARCHAR(128)
DECLARE @SQL VARCHAR(254)
SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] IN (N'FN', N'IF', N'TF', N'FS', N'FT') AND category = 0 ORDER BY [name])
WHILE @name IS NOT NULL
BEGIN
    SELECT @SQL = 'DROP FUNCTION [dbo].[' + RTRIM(@name) +']'
    EXEC (@SQL)
    PRINT 'Dropped Function: ' + @name
    SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] IN (N'FN', N'IF', N'TF', N'FS', N'FT') AND category = 0 AND [name] > @name ORDER BY [name])
END
GO
/* Drop all Foreign Key constraints */
DECLARE @name VARCHAR(128)
DECLARE @constraint VARCHAR(254)
DECLARE @SQL VARCHAR(254)
SELECT @name = (SELECT TOP 1 TABLE_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'FOREIGN KEY' ORDER BY TABLE_NAME)
WHILE @name is not null
BEGIN
    SELECT @constraint = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'FOREIGN KEY' AND TABLE_NAME = @name ORDER BY CONSTRAINT_NAME)
    WHILE @constraint IS NOT NULL
    BEGIN
        SELECT @SQL = 'ALTER TABLE [dbo].[' + RTRIM(@name) +'] DROP CONSTRAINT [' + RTRIM(@constraint) +']'
        EXEC (@SQL)
        PRINT 'Dropped FK Constraint: ' + @constraint + ' on ' + @name
        SELECT @constraint = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'FOREIGN KEY' AND CONSTRAINT_NAME <> @constraint AND TABLE_NAME = @name ORDER BY CONSTRAINT_NAME)
    END
SELECT @name = (SELECT TOP 1 TABLE_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'FOREIGN KEY' ORDER BY TABLE_NAME)
END
GO
/* Drop all Primary Key constraints */
DECLARE @name VARCHAR(128)
DECLARE @constraint VARCHAR(254)
DECLARE @SQL VARCHAR(254)
SELECT @name = (SELECT TOP 1 TABLE_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' ORDER BY TABLE_NAME)
WHILE @name IS NOT NULL
BEGIN
    SELECT @constraint = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' AND TABLE_NAME = @name ORDER BY CONSTRAINT_NAME)
    WHILE @constraint is not null
    BEGIN
        SELECT @SQL = 'ALTER TABLE [dbo].[' + RTRIM(@name) +'] DROP CONSTRAINT [' + RTRIM(@constraint)+']'
        EXEC (@SQL)
        PRINT 'Dropped PK Constraint: ' + @constraint + ' on ' + @name
        SELECT @constraint = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' AND CONSTRAINT_NAME <> @constraint AND TABLE_NAME = @name ORDER BY CONSTRAINT_NAME)
    END
SELECT @name = (SELECT TOP 1 TABLE_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' ORDER BY TABLE_NAME)
END
GO
/* Drop all tables */
DECLARE @name VARCHAR(128)
DECLARE @SQL VARCHAR(254)
SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'U' AND category = 0 ORDER BY [name])
WHILE @name IS NOT NULL
BEGIN
    SELECT @SQL = 'DROP TABLE [dbo].[' + RTRIM(@name) +']'
    EXEC (@SQL)
    PRINT 'Dropped Table: ' + @name
    SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'U' AND category = 0 AND [name] > @name ORDER BY [name])
END
GO