Doubts about QString manipulation

[Swati777999]

I've written the following code-

Line 1 : QString myStr = "3.1415161718";
Line 2 : int sz = myStr.size();  //sz=12
Line 3:  qDebug()<<"last digit ="<<myStr[sz-1]; // prints -> last digit = '8'
Line 4: QString last_dig=myStr[sz-1]  //this line gives error

Line 3 works perfectly whereas Line 4 gives an error. So, how can I store the required element of a string in another string?

Edit:
I tried the above code with the following condition, it gives me the message Condition satisfied even when the condition is not met.

if (myStr[sz-1]<5)
   qDebug()<<"Condition satisfied";

I tried to convert it to int and wrote the following code:

if (myStr[sz-1].toInt()<5)   
   qDebug()<<"Condition satisfied";

This gave me error.

[Sivan]

@Swati777999 QString's [] operator gives u QChar or QCharRef. You can't assign them straight to a QString. If you want to get the character as digit, you can do

int last_digit = myStr[zi-1].digitValue();

Or if you really want them in string

QString last_digit(myStr[zi-1]);

[JKSH]

@Swati777999 said in Doubts about QString manipulation:

Line 4: QString last_dig=myStr[sz-1]  //this line gives error

What does the error message say?

[Swati777999]

@JKSH said in Doubts about QString manipulation:

@Swati777999 said in Doubts about QString manipulation:

Line 4: QString last_dig=myStr[sz-1]  //this line gives error

What does the error message say?

It says no viable conversion from 'QCharRef' to 'QString' .

[JKSH]

@Swati777999 said in Doubts about QString manipulation:

It says no viable conversion from 'QCharRef' to 'QString' .

https://doc.qt.io/qt-5/qstring.html#QString-8 -- QString constructors can take QChar, but not QCharRef.

You are using the version of operator[] that returns a QCharRef: https://doc.qt.io/qt-5/qstring.html#operator-5b-5d

So, you can convert your QCharRef to a QChar first.

[Sivan]

@Swati777999 QString's [] operator gives u QChar or QCharRef. You can't assign them straight to a QString. If you want to get the character as digit, you can do

int last_digit = myStr[zi-1].digitValue();

Or if you really want them in string

QString last_digit(myStr[zi-1]);

[Swati777999]

@JKSH
This seems a lil complicated to me. Is not it going to be lengthy?

[Swati777999]

@Sivan Thanks! This worked for me. :)