Archivo de la etiqueta: Desarrollo Web

Complementos web y tutoriales

Aqui dejo informacion de una pagina que te revela el nombre de cada color hexadecimal:

Pagina web para construccion de estructuras en bootstrap

informacion: Bootstrap Carousel remove auto slide:

get rid also of the data-ride="carousel" … and correct syntax for inline: data-interval="false" (funciona)

Fuente original:

Codigo fuente de Tab-pane: bootstrap 4.2

Uso de sqltransation, rollback and commit vb


Para poder evitar que se graben cosas malas en tus tablas debes hacer rollback antes de cualquier commit para asi revertir los cambios y evitar información defectuosa en tu base de datos.

The following example creates a T:System.Data.SqlClient.SqlConnection and a T:System.Data.SqlClient.SqlTransaction. It also demonstrates how to use the M:System.Data.SqlClient.SqlConnection.BeginTransaction, M:System.Data.SqlClient.SqlTransaction.Commit, and M:System.Data.SqlClient.SqlTransaction.Rollback methods. The transaction is rolled back on any error. Try/Catch error handling is used to handle any errors when attempting to commit or roll back the transaction.

Private Sub ExecuteSqlTransaction(ByVal connectionString As String)
    Using connection As New SqlConnection(connectionString)

        Dim command As SqlCommand = connection.CreateCommand()
        Dim transaction As SqlTransaction

        ' Start a local transaction
        transaction = connection.BeginTransaction("SampleTransaction")

        ' Must assign both transaction object and connection
        ' to Command object for a pending local transaction.
        command.Connection = connection
        command.Transaction = transaction

            command.CommandText = _
              "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')"
            command.CommandText = _
              "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')"


            ' Attempt to commit the transaction.
            Console.WriteLine("Both records are written to database.")

        Catch ex As Exception
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType())
            Console.WriteLine("  Message: {0}", ex.Message)

            ' Attempt to roll back the transaction.

            Catch ex2 As Exception
                ' This catch block will handle any errors that may have occurred
                ' on the server that would cause the rollback to fail, such as
                ' a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType())
                Console.WriteLine("  Message: {0}", ex2.Message)
            End Try
        End Try
    End Using
End Sub



Darle estilo a input type=file

Mejor respuesta:

.file-input {
  visibility: hidden;
  width: 0;
  position: relative;
.file-input::before {
  content: 'Select some files';
  display: inline-block;
  background: -webkit-linear-gradient(top, #f9f9f9, #e3e3e3);
  border: 1px solid #999;
  border-radius: 3px;
  padding: 5px 8px;
  outline: none;
  white-space: nowrap;
  -webkit-user-select: none;
  cursor: pointer;
  text-shadow: 1px 1px #fff;
  font-weight: 700;
  font-size: 10pt;
  visibility: visible;
  position: absolute;
.file-input:hover::before {
  border-color: black;
.file-input:active::before {
  background: -webkit-linear-gradient(top, #e3e3e3, #f9f9f9);
<input type="file" accept="image/*"   class="file-input"/>

Fuente original: Dar Formato a Input Type=file