Programming Tutorials

Create a text file and write text programmatically The following asp.net c# example code demonstrates how we can create a text file and write text on it programmatically in the .net framework. We can get the application's physical path using HttpRequest.PhysicalApplicationPath property as Request.PhysicalApplicationPath. We also can get the file path by adding two strings, which are the physical application path and file name with extension. In this example, we created a text file name Text.txt and programmatically wrote two lines of text in this file at run time. StreamWriter Class allows us to implement a TextWriter for writing characters to a stream in a particular encoding. In this example code, we initialize a StreamWriter object. The File class’s CreateText(path) method creates or opens a file for writing UTF-8 encoded text. this method requires passing a parameter name 'path'. The path parameter value specifies the fi...

Array IndexOf() Method The following asp.net c# example code demonstrate us how can we get index of an array element programmatically at run timein an asp.net application. Array Class Array.IndexOf(Array, Object) overloaded method search for the specified object and returnthe index of its first occurrence in a one-dimensional array. Array.IndexOf(Array, Object) method has two required parameters named 'array' and 'value'. The 'array' parameter represent theone-dimensional array to search and 'value' parameter represent the object to locate in array. In this example code, we initializesa string array with elements and pass a string object as 'value' parameter value to IndexOf() method to get its index. Array.IndexOf() method return an integer value which represent the index of the first occurrence of specified object in array, if found;otherwise it return the lower bound of the array minus 1. The method thr...

DataBind a RadioButtonList with array The following ASP.NET C# example code demonstrates to us how can we data bind a RadioButtonList with an Array data source. RadioButtonList is an ASP.NET list web server control. RadioButtonList control renders a radio group on the web page. RadioButtonList’s each ListItem object renders a single RadioButton with the same group name. We can populate RadioButtonList items from various data sources such as SqlDataSource, ObjectDataSource, Array, ArrayList, Generic List, Dictionary, etc. The Array is a popular data source object to data bind with a list web server control such as RadioButtonList, BulletedList, ListBox, etc. Each element from the Array object creates a new ListItem object when we data bind a list server control with the Array data source. To populate a RadioButtonList with an Array data source is very simple in the ASP.NET C# environment. First, we need to create an Array object. Next, w...

DataBind a CheckBoxList with array The following ASP.NET C# example code demonstrates to us how can we data bind a CheckBoxList web server control programmatically at run time with an Array data source object. CheckBoxList is an ASP.NET list web server control. CheckBoxList allows web users to select/check one or more items at a time. CheckBoxList contains ListItem objects. Each ListItem object represents an item. We can populate a CheckBoxList from Array elements. To do this, first, we need to initialize an array object. Then we populate the Array with items (elements). Next, we need to specify the newly created Array as CheckBoxList control's DataSource. Finally, we can data bind CheckBoxList control with Array by calling the CheckBoxList DataBind() method. The populated CheckBoxlist creates the same number of items as the number of elements that exist in the Array. Each Array element creates an item in CheckBoxList. We populated CheckBoxL...

DataBind DropDownList with array The following asp.net c# example code demonstrates to us how can we populate a DropDownList server control with items from an Array data source. DropDownList is a list web server control. DropDownList can contain one or more ListItem objects. A ListItem object includes Text and an optional Value. The Array is the most preferable data source for .NET developers to populate a list server control. In this example code, we initialized a String data type Array object with items/elements. Then we set the DropDownList's DataSource property value to the newly initialized Array object. Next, we call the DropDownList DataBind() method to data bind DropDownList with the Array data source. Each element of the Array creates an item in DropDownList. This is a one-dimensional Array, so DropDownList's each ListItem object's 'Text' and 'Value' properties hold the same value; such as if Array'...

String Compare() Method - case insensitive/ ignore case The .NET C# developers can compare two specified String objects using the String class’s Compare() method. The String Compare() method returns an integer that indicates their relative position in the sort order. This method is overloaded. String Compare(String, String, Boolean) method overload compares two specified String objects by ignoring or honoring their case. So we can use this overloaded method to compare two string objects by ignoring case (case insensitive String comparison). This overloaded method requires three parameters. First, two parameters are two String objects those we need to compare. And third parameter is a Boolean value. We must set the Boolean parameter value to True when we need to ignore the case during comparison. Or we must set the Boolean parameter value to False to respect the case during String comparison. If the method returned integer is less than zero, then the fir...

String Compare() Method - case sensitive The .NET framework has many methods to properly manipulate String. String Compare() method allows us to compare two String objects. This method is overloaded for various support such as we can compare strings by ignoring or honoring cases, we also can use culture-specific information to influence the comparison. String class’s Compare(String, String, Boolean) overloaded method allows us to compare two string objects by honoring their case (case-sensitive string comparison). First, two parameters are two String objects that we want to compare and the third parameter is a Boolean value name ignoreCase. This Boolean parameter value False specifies the method to honor the case of the string during comparison. This method return value is a 32-bit signed integer that indicates the relationship between the two string objects. If the return value is less than zero then the first string is less than the second String. Ret...

String Join() Method The following asp.net c# example code demonstrate us how can we use .net framework's String Class Join() method in an asp.net application. String.Join() method allow us to concatenate the elements of a specified array or the members of a collection, using the specified separator between each element or member. This member is overloaded, those are String.Join(String, IEnumerable<String>), Join<T>(String, IEnumerable<T>), Join(String, Object[]), Join(String, String[]) and Join(String, String[], Int32, Int32). In this tutorial, we only discuss about String.Join(String, String[]) overloaded method. String.Join(String, String[]) method concatenate all the elements of a string array, using the specified separator between each element. This method require to pass two parameters named 'separator' and 'value'. The 'separator' parameter value represent a string to use as a separator and 'value...

String Split() Method The following asp.net c# example code demonstrates to us how can we split a String by specified delimiter and populate an array with splitter elements programmatically at run time in an asp.net application. The .net framework String Class represents text as a series of Unicode characters. The String class’s Split() method returns a new String Array that contains the substrings in this instance that are delimited by elements of a specified String or Unicode character Array. This member is overloaded, those are Split(Char[]), Split(Char[], Int32), Split(Char[], StringSplitOptions), Split(Char[], Int32, StringSplitOptions) and Split(String[], Int32, StringSplitOptions). In this example, we only discuss the Split(Char[]) overloaded method. The Split(Char[]) method returns a string array that contains the substrings in this instance that are delimited by elements of a specified Unicode character array. This method requires passing a param...

String Replace() Method In the .net framework, we can replace a string or a substring from a specified string with another string. The String Replace(String, String) method allows us to replace a string with another string. This method returns a new string in which all occurrences of a specified string in the current instance are replaced with another specified string. Replace method requires two parameters. Both parameters type is System.String. The first parameter's name is oldValue that the string to be replaced. And the second parameter's name is newValue where the string replaces all occurrences of the old value. If the method does not find oldValue in the current instance then it returns the current instance unchanged. Otherwise, it replaces the string with a specified string and returns a new string. This method performs an ordinal (case sensitive and culture insensitive) search to find oldValue. String.Replace(Char, Char) method returns a ...

String ToUpper() Method The String represents text as a series of Unicode characters. String class’s ToUpper() method return a copy of the String converted to uppercase. This method is overloaded, those are ToUpper() and ToUpper(CultureInfo). String ToUpper() method is in the System namespace and its return value type is a String. That returned 'string' is uppercase characters equivalent to the specified String. This ToUpper() method uses the casing rules of the current culture to convert each character to an uppercase equivalent. The ToUpper() method does not modify the specified String instance, it just returns a new String instance in which all characters are converted to uppercase from the specified String. The string ToUpper(CultureInfo) method returns a copy of the specified String converted to uppercase, using the casing rules of the specified culture. The following .NET C# example code demonstrates to us how can we convert a String to uppe...

String Substring() Method The .net String class’s Substring() method allows us to retrieve a substring from a String object. This method has two overloaded methods those are Substring(Int32) and Substring(Int32, Int32). The Substring(Int32) overloaded method retrieves a substring from a String by starting at a specified character position and continuing to the end of the String. This method needs to pass a parameter name startIndex. This parameter data type is Int32. The startIndex parameter value specifies a zero-based starting character position of the String. This method does not modify the current string instance, it returns a new String that begins at the startIndex position of the current String. The Substring(Int32, Int32) overloaded method allows us to get a substring from a String that starts a specified character position String and has a specified length. This method has two parameters, which are startIndex and length. The startIndex is the zer...

Convert.ToInt32() Method - Convert string to numeric value The .NET Convert class allows us to convert a base data type to another base data type. Convert class ToInt32(String) method converts the specified string representation of a number to an equivalent 32-bit signed integer. Convert class’s ToInt32(String) overloaded method requires passing a parameter. This parameter name is 'value' which data type is String. This parameter passes the String that contains the number to convert. This method returns a 32-bit signed integer that is equivalent to the number in value. If the parameter value is null then the method returns zero (0). We also can convert a string object to a numeric value (int 32-bit integer) by using Int32 Parse(String) method or Int32 TryParse() method. Int32 TryParse() method returns an additional value that indicates whether the conversion succeeded. The following ASP.NET C# example code demonstrates to us how can we convert a...

Get days in month DateTime.DaysInMonth() method return the number of days in the specified month and year. this method exists in System namespace.DateTime.DaysInMonth(year, month) method require to pass two parameters named 'year' and 'month'. the 'year' parameter valuedata type is System.Int32 which represent the specified year. the 'month' parameter value data type also System.int32 which representa month number ranging from 1 to 12. This method return value data type is System.Int32 which represent the number of days in specified month for the specified year. this is very useful method to get the number of days in February month in a specified year which depend on leap year. The following asp.net c# example code demonstrate us how can we get days (count number of days) in a specified month and year programmaticallyat run time in an asp.net application. DaysInMonth.aspx <%@ Page Language="C#" ...

Get time of day The following ASP.NET C# c# example code demonstrates to us how we can get the time from a DateTime object. The DateTime object represents an instance in time typically expressed as a date and time of day. The DateTime object exists in the .NET System namespace. DateTime Now property gets a DateTime object that is set to the current date and time on a web server, expressed as the local time. In this example code at first, we create a DateTime variable and assign value by using the DateTime Now property. Finally, we extract the time object from the DateTime variable by DateTime TimeOfDay property. TimeOfDay property gets a time interval that represents the fraction of the day that has elapsed since midnight from a DateTime object. This property value type is System.TimeSpan. So using the DateTime TimeOfDay property we can get the time from a DateTime object. The TimeSpan object represents a time interval. We can display th...

Subtract two DateTimes The following ASP.NET C# example code demonstrates to us how can we subtract two DateTime objects programmatically at run time in an asp.net application. The .NET framework's DateTime Subtract() method allows us to subtract the specified time or duration from this instance. DateTime Subtract() method is overloaded, those are Subtract(DateTime) and Subtract(TimeSpan). DateTime Subtract(DateTime) overloaded method subtracts the specified date and time from the instance. We need to pass a DateTime object to this method as a parameter. This method returns a TimeSpan value. The return TimeSpan object represents a time interval that is equal to the date and time of the instance minus the date and time of the parameter. DateTime Subtract(TimeSpan) overloaded method subtracts the specified duration from this instance. This method is required passing a TimeSpan object as the parameter. The TimeSpan represents the time interva...

Days between two DateTimes The following asp.net c# example code demonstrate us how can we get total days difference between two DateTime objectsprogrammatically at run time in an asp.net application. DateTime.Subtract(DateTime) method allow us to subtract the specified date and time from this instance. We just need to passa DateTime object as parameter to subtract from specified DateTime object. DateTime.Subtract(DateTime) method return aSystem.TimeSpan type value. This TimeSpan value represents a time interval that is equal to the date and time of instance minusdate and time of parameter. TimeSpan.TotalDays property get the value of the current TimeSpan structure expressed in whole and fractional days. TimeSpan.Days property get the days component of the time interval represented by the current TimeSpan structure. This property doesnot return any fractional day, it just return full day part from a TimeSpan object. Result can be negative ...

Hours between two DateTimes The following asp.net c# example code demonstrate us how can we get number of hours between two DateTimeobjects programmatically at run time in an asp.net application. .Net framework's DateTime Class DateTime.Subtract(DateTime) overloaded method allow us to subtract a specifieddate and time from this instance. DateTime.Subtract() method need to pass a DateTime object to subtract from specifiedDateTime object. This method return a System.TimeSpan value. This TimeSpan represent a time interval that is equalto the date and time represented by this instance minus the date and time passed by parameter. TimeSpan.TotalHours property allow us to get the value of the current TimeSpan structure expressed in wholeand fractional hours. TimeSpan.Hours property allow us to get the hours component of the time interval represented by the currentTimeSpan structure. This property return value type is System.Int32. ...

DateTime AddMilliseconds() Method The following asp.net c# example code demonstrate us how can we add specified number of Milliseconds witha DateTime object programmatically at run time. .Net framework's DateTime Class DateTime.AddMilliseconds() methodreturn a new DateTime object that add the specified number of milliseconds to the value of this instance. DateTime.AddMilliseconds() method require to pass a parameter named 'value'. The 'value' parameter data type isSystem.Double which represent a number of whole and fractional milliseconds. This parameter value can be negative orpositive. So, we can technically add or subtract number of milliseconds from a DateTime instance. This parameter valueis rounded to the nearest integer. DateTime.AddMilliseconds() method return value data type is System.DateTime. This return DateTime value is sum ofthe date and time represented by this instance and the number of milliseconds passed by ...

DateTime AddYears() Method The following asp.net c# example code demonstrate us how can we add one or more years with aDateTime object programmatically at run time in an asp.net application. .Net framework's DateTime Classhas a built in method to add years with a date. DateTime.AddYears() method return a new DateTime object that add the specified number of years to the valueof this instance. This method require to pass a parameter named 'value'. The 'value' parameter data type isSystem.Int32. This integer value represent a number of years to add with specified DateTime object. This isinteresting that this parameter can be negative or positive. So, technically we can subtract years from a DateTime object. DateTime.AddYears() method return value data type is System.DateTime. The return value represent a DateTime that is the sum ofthe date and time of this instance and the number of years pass by parameter. DateTime.AddYea...

DateTime AddMonths() Method The following asp.net c# example code demonstrate us how can we add specified months with a DateTime objectprogrammatically at run time in an asp.net application. .Net framework's has a built in method DateTime.AddMonths()to add one or more months with a DateTime instance. DateTime.AddMonths() method return a new DateTime object that add the specified number of months to the valueof this instance. This method require to pass a parameter named 'months'. The 'months' parameter value data typeis System.Int32. This integer value represent a number of months to add with a date. This parameter value can be negative orpositive. So, we can technically add or subtract/remove months from a date. DateTime.AddMonths() method return a value which data type is System.DateTime. This return value is the sum of the date andtime represented by this instance and number of months passed by parameter. DateTime....

DateTime AddHours() Method The following ASP.NET C# example code demonstrates to us how can we add one or more hours to a DateTime object programmatically at run time. The .Net framework's DateTime AddHours() method returns a new DateTime object that adds the specified number of hours to the value of this instance. DateTime AddHours() method has a required parameter. This parameter name is value and its data type is a Double. This Double value represents the number of whole and fractional hours. This parameter value can be negative or positive. So, we can also subtract hours from a DateTime object if we pass a negative value as the parameter. DateTime AddHours() method returns a DateTime object. The return DateTime object is the sum of the DateTime instance and the number of hours passed by the parameter. The fractional part of the value parameter value is the fractional part of an hour. Such as the Parameter value 5.5 is equivalent to 5 hou...

DateTime AddMinutes() Method The following ASp.NET C# example code demonstrates to us how can we add minutes to a DateTime object programmatically at run time. The .Net framework's DateTime AddMinutes() method allows us to add one or more minutes with a DateTime object. DateTime AddMinutes() method exists in the System namespace. AddMinutes() method has a required parameter named value. This value parameter data type is a Double which represents a number of whole and fractional minutes. This is very useful in that the value parameter value can be negative or positive. So, technically we can also subtract minutes from a DateTime object. DateTime AddMinutes() method returns value data type is System.DateTime. This return value is a DateTime object which is the sum of specified minutes passed by the parameter and specified DateTime object. AddMinutes() method does not modify/change the provided DateTime object instead it returns a new DateTime ...

Add days to a DateTime object In the .NET framework, there are many built-in methods and properties are exists to manage DateTime objects. DateTime AddDays() method returns a new DateTime that adds the specified number of days to the value of this DateTime object instance. This method requires passing a parameter. This parameter name is 'value' and its data type is Double. This value parameter passes a number of whole and fractional days. This value parameter can be a negative or positive number. DateTime AddDays() method returns a System.DateTime type value. Return DateTime object is the sum of provided DateTime instance and the number of days passes by the parameter. This method does not modify the provided DateTime object instead it returns the result as a new DateTime object. The following ASP.NET C# example code demonstrates to us how can we add days with a DateTime object in the .NET framework. DateTimeAddDays.asp...