I'm getting user input from a box in the unreal engine landscape import pane and would like to be able to convert that input to a float. Currently, the text comes in as FText
I've tried casting the resulting FText to float and using the built-in FText::toNumber.
I would like to be able to do something like:
FText mapDeltaX = GetPropertyValueText(PropertyHandle_Scale_X);
float deltaX = (float)mapDeltaX;
But unfortunately I get the error no suitable conversion from "FText" to "float" exists.
You can convert TCHAR* to float using
FCString::Atof(*String);
So in your case you'd convert your FText to FString, then to float:
FCString::Atof(*mapDeltaX.ToString());
Related
I'm using c++ and I'm trying to convert a string to double, the string is given to me as an input in the form: "xx.yy", and it should stay that way, meaning no more than two digits after the dot.
I've tried atof and strod but outcome was no good, plus i can't use anything to spectacular' because it's for a course and no one will belive me
str_db = strtod(ptr, NULL);
item->price = str_db;
str_db is type double.
Thank you.
Is it not reccomended to convert a string in such way:
string input = "81.312";
double val = atof(input.c_str());
DO NOT use std::atof in C++. That doesn't check for input error.
Use std::stod. That checks for error also and throws exception accordingly.
Also, it takes std::string const & as argument. So you don't have to pass input.c_str(). Just do this:
double value = std::stod(input);
It is not wrong, but more right would be to use boost::lexical_cast.
You should also check if these tools handle NANs and INFs correctly.
I'm basically trying to write a basic converter in visual studio 2008, and I have 2 text boxes, one which gets input from the user, and one which gives output with the result. When I press the button I want the input from the first textbox to multiply by 4.35 then display in the 2nd textbox. This is my code in the button code so far:
String^ i1 = textBox1->Text;
float rez = (i1*4.35)ToString;
textBox2->Text = rez;
However I'm getting these errors:
f:\microsoft visual studio 9.0\projects\hellowin\hellowin\Form1.h(148) : error C2676: binary '*' : 'System::String ^' does not define this operator or a conversion to a type acceptable to the predefined operator
f:\microsoft visual studio 9.0\projects\hellowin\hellowin\Form1.h(148) : error C2227: left of '->ToString' must point to class/struct/union/generic type
f:\microsoft visual studio 9.0\projects\hellowin\hellowin\Form1.h(149) : error C2664: 'void System::Windows::Forms::Control::Text::set(System::String ^)' : cannot convert parameter 1 from 'float' to 'System::String ^'
Please help I'm going insane on how ridiculously difficult it is to get some input from a textbox in C++. I've googled every error I had and nothing useful came up, I've been searching answers for an hour already, please help.
Fixing it for you,
String^ i1 = textBox1->Text;
float rez = (float)(Convert::ToDouble(i1)*4.35);
textBox2->Text = rez.ToString();
Basically, you want to convert your string to an actual number, do the math, and then make it back into a string for displaying purposes.
You're trying to multiply a string by a double and there is no operator that defines how to do that. You need to convert your string to a double first, and then use that in the calculation.
Then, you're trying to assign a string to a float, which again is nonsense.. You need to calculate the float, then convert it to a string when assigning it to the textbox text field.
Something like:
String^ i1 = textBox1->Text;
float rez = (Convert::ToDouble(i1)*4.35);
textBox2->Text = rez.ToString();
to parse a NSString i have used this :
NSString *adress=[stations objectForKey:#"adress_station"];
what about a float, how should i call it, i try to do that :
float distance=[stations objectForKey:#"distance"];
but i have got an error :
incompatible type in initialization
i don't want to put it in NSString, i need it as float because i need it in other operations :)
float distance = [[stations objectForKey:#"distance"] floatValue];
objectForKey returns an object (in this case I assume an NSString).
Calling -floatValue on an NSString will get the data as a float.
how can I convert a CString variable to a floating point?
(I'm using visuall c++ 6.0 and the MFC)
I'm trying to use an edit box to return a value which I'm putting into an array of floating points. I'm Using the GetWindowText method to get the value, which returns a CString. So I need to convert to a floating point. (or am I just doing things completely the wrong way?).
I presume there are methods for doing this already in the MFC.(have already used the Format method to convet to a CString display the values in the array in the edit box)
Thanks.
you can just do
CString pi = "3.14";
return atof(pi);
EDIT
Also use this function:
CString pi = "3.14";
return _ttof(pi);
Reading a string value and parse/convert it to float allows you to locate the error when there is one. All you need is a help of a C Run-time function: strtod() or atof().
I would prefer strtod as the second argument returns a pointer to the string where the parse terminated:
CString str;
m_edtMyEditBox.GetWindowText(str);
char *pEnd;
double dValue = strtod(str.GetBuffer(str.GetLength()), &pEnd);
if (*pEnd != '\0')
{
// Error in parsing
}
str.ReleaseBuffer();