Predicate: c# - String to Generic Type conversion

Lately I was searching about how to convert a string to another type, which is specified as Generic.

The solution is very simple and already present in the framework:



public static T To(this string text)
{
return (T)Convert.ChangeType(text, typeof(T));
}
// sample usage
int val = "124".To();
double dbl = "124.5".To();

Crazy, isNumeric in all languages

http://rosettacode.org/wiki/Determine_if_a_string_is_numeric

new to VS 2008

http://www.c-sharpcorner.com/UploadFile/john_charles/WhatnewinVisualStudioNET200802012008121831PM/WhatnewinVisualStudioNET2008.aspx

.net anonymous method

we can do edit and continue feature in a method which had anonymous calls .

for example: method which contain delegate calls

Constant Pointers and Pointers to Constants

Pointer contants and contant pointers are also something that many people simply don't use. If you have a value in your program and it should not change, or if you have a pointer and you don't want it to be pointed to a different value, you should make it a constant with the const keyword.

There are generally two places that the const keyword can be used when declaring a pointer. Consider the following declaration:

char A_char = 'A'; char * myPtr = &A_char; 

This is a simple declaration of the variable myPtr. myPtr is a pointer to a character variable and in this case points to the character 'A'.

Don't be confused about the fact that a character pointer is being used to point to a single character—this is perfectly legal! Not every character pointer has to point to a string.

Now consider the following three declarations assuming that char_A has been defined as a type char variable.:

const char * myPtr = &char_A; char * const myPtr = &char_A; const char * const myPtr = &char_A; 

What is the difference between each of the valid ones? Do you know?

They are all three valid and correct declarations. Each assigns the addres of char_A to a character pointer. The difference is in what is constant.

The first declaration:

const char * myPtr

declares a pointer to a constant character. You cannot use this pointer to change the value being pointed to:

char char_A = 'A'; const char * myPtr = &char_A; *myPtr = 'J';    // error - can't change value of *myPtr 

The second declaration,

char * const myPtr

declares a constant pointer to a character. The location stored in the pointer cannot change. You cannot change where this pointer points:

char char_A = 'A'; char char_B = 'B';  char * const myPtr = &char_A; myPtr = &char_B;    // error - can't change address of myPtr 

The third declares a pointer to a character where both the pointer value and the value being pointed at will not change.

Pretty simple, but as with many things related to pointers, a number of people seem to have trouble.

ref# http://www.codeguru.com/cpp/cpp/cpp_mfc/general/article.php/c6967/