You can use the parseInt() and parseFloat() methods. Notice that extra letters following a valid number are ignored, which is kinda wierd but convenient at times.

I am including the header file <string>, and I am using the string class, but the code doesn't compile? (namespace resolution, having the std:: topics) How do I use unique() with vectors? (answered only once, but still a good question to have due to people not knowing that it's possible to do)

There are two easy ways to do this: you can use the <cstdio> facilities or the <iostream> library. In general, you should prefer the <iostream> library.

Javascript variables are loosely typed: the conversion between a string and a number happens automatically. Since plus (+) is also used as in string concatenation, '1' + 1 is equal to '11' : the String deciding what + does. To overcome this, first convert the string to a number. For example: +varname or Number(varname) or parseInt(varname, 10) or parseFloat(varname) . Prompt and form control values are strings, as is the result from a prompt window.

You can manipulate cookies in JavaScript with the document.cookie property. You can set a cookie by assigning this property, and retrieve one by reading its current value.

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Private Sub ddlCulture_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ddlCulture.SelectedIndexChanged

Well, printf does it for output, so look at its related function named sprintf that "prints formated output to a string."

It's easy. Use sprintf. For example: char string1[50]; char string2[50]; short int var1; float var2; ... sprintf (string1, "%d", var1); sprintf (string2, "%f", var2);

You want to make a function that converts from a type to another. Like from std::string to int, or the other way around. This can be done using std::stringstream and insertion / extraction operators. Just as above, templates will prove of great help: Its usage is not as straightforward as the above explained max template. Normally, you would want to call it like "int value = lexical_cast( myStdString );". There is, however, a problem.

If you are reading a host's address from the command line, you may not know if you have an aaa.bbb.ccc.ddd style address, or a host.domain.com style address. What I do with these, is first try to use it as a aaa.bbb.ccc.ddd type address, and if that fails, then do a name lookup on it. Here is an example: Converts ascii text to in_addr struct. NULL is returned if the address can not be found.

Example: To convert 49 degrees 30 minutes and 45 seconds to decimal degrees: dn = 49 + 30/60 + 45/3600 = 49.5125 Note that int(n) denotes taking the integer part of a number (e.g. int(49.5125) = 49) and frac its fractional part (e.g. frac(49.5125) = 0.5125). mi is an intermediate result. Example: To convert 49.5125 decimal degrees to degrees, minutes and seconds: d = int(49.5125) = 49 mi= frac(49.5125)*60 = 0.5125*60 = 30.75 m = int(mi) = int(30.75) = 30 s = frac(mi)*60 = 0.

Use the parseInt() function, that takes a string as the first parameter, and the base as a second parameter. So to convert hexadecimal 3F to decimal, use parseInt ("3F", 16);

In general, when you want to convert from one type to another, the first class to look at is System.Convert. It has a load of static methods which are likely to help you. If you're converting from a String, you could also check whether the type that you want to convert to has a Parse method or something similar - for instance, I usually use DateTime.ParseExact to convert from a String to a DateTime.

Some libraries have routines strupr and strlwr or strupper and strlower, but these are not Standard or portable. It's a straightforward exercise to write upper/lower-case functions in terms of the toupper and tolower macros in <ctype.h>; see also question 13.5. (The only tricky part is that the function will either have to modify the string in-place or deal with the problem of returning a new string; see question 7.5a.

There are several ways. The most straightforward is: String myString = numString.trim(); int i = Integer.parseInt(myString); long l = Long.parseLong(myString) or String myString = numString.trim(); i = Integer.parseInt(myString,myIntRadix); Note 1: There is a gotcha with parseInt - it will throw a NumberFormatException for String values in the range "80000000" to "ffffffff". You might expect it to interpret them as negative, but it does not. The values have to be "-80000000" .

Try any of these: String s = String.valueOf(i); or String s = Integer.toString(i); or String s = Integer.toString(i, radix); or // briefer but may result in extra object allocation. String s = "" + i; Note: There are similar classes for Double, Float, Long, etc.

OCTET STRING value like 73:63:6f:74:74:79 can be converted into a readable string (DisplayString) by formatting it according to the DisplayString textual convention.

To do something interesting with HTML elements, we must first be able to uniquely identify which element we want. In the example lt;input type="button" id="useless" name="mybutton" value="doNothing" />