Should i use aspx or razor

However, you generally don't have to specify a type for a variable. Most of the time, ASP. NET can figure out the type based on how the data in the variable is being used. Occasionally you must specify a type; you'll see examples where this is true.

You declare a variable using the var keyword if you don't want to specify a type or by using the name of the type:. Although ASP. NET can usually determine a data type automatically, sometimes it can't.

Therefore, you might need to help ASP. NET out by performing an explicit conversion. Even if you don't have to convert types, sometimes it's helpful to test to see what type of data you might be working with.

The most common case is that you have to convert a string to another type, such as to an integer or date. The following example shows a typical case where you must convert a string to a number.

As a rule, user input comes to you as strings. Even if you've prompted users to enter a number, and even if they've entered a digit, when user input is submitted and you read it in code, the data is in string format.

Therefore, you must convert the string to a number. In the example, if you try to perform arithmetic on the values without converting them, the following error results, because ASP. NET cannot add two strings:. To convert the values to integers, you call the AsInt method. If the conversion is successful, you can then add the numbers.

Converts a string that has a decimal value like "1. NET, a decimal number is more precise than a floating-point number. Converts a string that represents a date and time value to the ASP. NET DateTime type.

An operator is a keyword or character that tells ASP. NET what kind of command to perform in an expression. The C language and the Razor syntax that's based on it supports many operators, but you only need to recognize a few to get started.

The following table summarizes the most common operators. Returns true if the values are equal. Concatenation, which is used to join strings. NET knows the difference between this operator and the addition operator based on the data type of the expression.

Reverses a true value to false and vice versa. Typically used as a shorthand way to test for false that is, for not true. You'll often work with file and folder paths in your code. Here is an example of physical folder structure for a website as it might appear on your development computer:. Virtual folder paths always use forward slashes. The virtual path of a folder doesn't have to have the same name as the physical folder; it can be an alias.

On production servers, the virtual path rarely matches an exact physical path. When you work with files and folders in code, sometimes you need to reference the physical path and sometimes a virtual path, depending on what objects you're working with. NET gives you these tools for working with file and folder paths in code: the Server. The Server. You use this method any time you need a complete physical path. A typical example is when you're reading or writing a text file or image file on the web server.

You typically don't know the absolute physical path of your site on a hosting site's server, so this method can convert the path you do know — the virtual path — to the corresponding path on the server for you. You pass the virtual path to a file or folder to the method, and it returns the physical path:. This is very handy because you can move pages around in a site, and any links they contain to other pages won't be broken. It's also handy in case you ever move your website to a different location.

Here are some examples:. NET will treat these paths when the page runs:. You won't actually see these paths as the values of the variable, but ASP.

NET will treat the paths as if that's what they were. When the page runs, ASP. NET server code lets you perform tasks based on conditions and write code that repeats statements a specific number of times that is, code that runs a loop. To test a simple condition you use the if statement, which returns true or false based on a test you specify:. The if keyword starts a block.

The actual test condition is in parentheses and returns true or false. The statements that run if the test is true are enclosed in braces. An if statement can include an else block that specifies statements to run if the condition is false:. In this example, if the first condition in the if block is not true, the else if condition is checked.

If that condition is met, the statements in the else if block are executed. If none of the conditions are met, the statements in the else block are executed. You can add any number of else if blocks, and then close with an else block as the "everything else" condition. The value to test is in parentheses in the example, the weekday variable. Each individual test uses a case statement that ends with a colon :.

If the value of a case statement matches the test value, the code in that case block is executed. You close each case statement with a break statement. If you forget to include break in each case block, the code from the next case statement will run also. A switch block often has a default statement as the last case for an "everything else" option that runs if none of the other cases are true.

You often need to run the same statements repeatedly. You do this by looping. For example, you often run the same statements for each item in a collection of data. If you know exactly how many times you want to loop, you can use a for loop. This kind of loop is especially useful for counting up or counting down:. The loop begins with the for keyword, followed by three statements in parentheses, each terminated with a semicolon. Inside the braces is the code that will run for each iteration of the loop.

When you run this page, the example creates 11 lines displaying the output, with the text in each line indicating the item number. If you're working with a collection or array, you often use a foreach loop. A collection is a group of similar objects, and the foreach loop lets you carry out a task on each item in the collection.

This type of loop is convenient for collections, because unlike a for loop, you don't have to increment the counter or set a limit. Instead, the foreach loop code simply proceeds through the collection until it's finished. For example, the following code returns the items in the Request.

ServerVariables collection, which is an object that contains information about your web server. The foreach keyword is followed by parentheses where you declare a variable that represents a single item in the collection in the example, var item , followed by the in keyword, followed by the collection you want to loop through.

In the body of the foreach loop, you can access the current item using the variable that you declared earlier. A while loop begins with the while keyword, followed by parentheses where you specify how long the loop continues here, for as long as countNum is less than 50 , then the block to repeat. Loops typically increment add to or decrement subtract from a variable or object used for counting. Nearly everything in an ASP. NET website is an object, including the web page itself. This section discusses some important objects you'll work with frequently in your code.

The most basic object in ASP. NET is the page. You can access properties of the page object directly without any qualifying object. The following code gets the page's file path, using the Request object of the page:. To make it clear that you're referencing properties and methods on the current page object, you can optionally use the keyword this to represent the page object in your code. Here is the previous code example, with this added to represent the page:. As you've already seen, this is a collection of information about the current request, including what type of browser made the request, the URL of the page, the user identity, etc.

This is a collection of information about the response page that will be sent to the browser when the server code has finished running. For example, you can use this property to write information into the response. A collection is a group of objects of the same type, such as a collection of Customer objects from a database.

NET contains many built-in collections, like the Request. Files collection. You'll often work with data in collections. Two common collection types are the array and the dictionary.

The file extension of a Razor view is cshtml for C and vbhtml for VB. By default all text from the expression is HTML encoded. Razor is not a new language. It is easy to learn. The main advantage of Razor, is that there is less transition between HTML and code because Razor provides an optimized syntax to generate HTML using a code focused templating approach. Loop and condition example with Razor View Engine:. Conclusion Razor provides a new view engine with streamlined code for focused templating.

Razor's syntax is very compact and improves readability of the markup and code. View All. Jignesh Trivedi Updated date Jan 25, Razor View Engine. Next Recommended Reading. Windows 10 Vs Windows Visual Studio Vs Visual Studio Or you can build your own if you have an interest in, and an aptitude for programming.

If you choose to build your own, you can choose from a wide range of programming languages and frameworks. If you are a beginner, you will probably want to start with a framework and language that is easy to learn, well supported and robust. If you are considering making a career as a programmer, you probably want to know that the skills you acquire while learning your new framework will enhance your value to potential employers.

In both cases, learning C as a language and ASP. NET Core as a framework will tick those boxes. If you are a seasoned developer, the Razor Pages framework is likely to add to your skillset with the minimum amount of effort.

You can still choose to use ASP. NET Core web applications. If you are porting an existing. Razor Pages is the default for building server-side web applications in ASP.

NET Core. What Is Razor Pages?