While playing in data tables in .net, it may require to have some temporary values such as records counts, primary key field name, …etc. In those situations, instead of declaring new variables in the program, it is ideal way to use “ExtendedProperties” option in datatable. The property is holding the collection (hashtable) values. Here is the syntax; DataTable.ExtendedProperties.Add (object key, object value); Examples; DataTable dtObj = new DataTable("employees"); dtObj.ExtendedProperties.Add("totalCount", 500); dtObj.ExtendedProperties.Add("primaryKey", "employee_id"); dtObj.ExtendedProperties.Add("createdDate", DateTime.Now); For retrieving assigned properties, int iCount = Convert.ToInt32(dtObj.ExtendedProperties["totalCount"].ToString()); So simple and effective property.
We might used the "Charactercasing" property of Textbox in C# windows applications. This is used to get the input values as upper or lower case without doing the separate coding. But in web applications,this property is not available directly. But we need to achieve this functionality using CSS. In CSS, we need to use the "text-transform" property to make the input text as upper, lower or initcaps. Here is the CSS sample: .makeuppercase { text-transform:uppercase; } .makelowercase { text-transform:lowercase; } .makeinitcaps { text-transform:capitalize; } Need to assign the style name to TextBox "CssClass" property as; TextBox1.CssClass = "makeuppercase" The above code will make the input values to upper case while entering the values.
We may need to store the images in the database. It is easy and pretty simple. The basic idea is; 1) The images are stored in database as bytes. In MySQL database we need to create a field/column of type " Blob ". 2) Need to use FileStream and BinaryReader objects to convert images into bytes. Here is the C# code, to do the task Table schema: C# code: MySqlConnection mcon = null; MySqlCommand cmd = null; FileStream fsObj = null; BinaryReader binRdr = null; try { //converting image to bytes fsObj = File.OpenRead(pictureBox1.ImageLocation); byte[] imgContent = new byte[fsObj.Length]; binRdr = new BinaryReader(fsObj); imgContent = binRdr.ReadBytes((int)fsObj.Length); mcon = new MySqlConnection("server=localhost;user=root;pwd=root;database=test;"); mcon.Open(); //inserting into MySQL db cmd = new MySqlCommand("insert into users (userid,username,userphoto) values (@userid, @username, @userphoto)", mcon); cmd.Parameters.Add(new MySqlPara...
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