将项目添加到列表框的按钮出现错误

Question

so i made a simple program in mfc dialog in c++ which has an add button, a remove button, a listbox, and an edit box. i want to be able to type something into the editbox, then click the add button and it will get added to the listbox. but i am getting this error:

Error 1 error C2679: binary '=' : no operator found which takes a right-hand operand of type 'CEdit' (or there is no acceptable conversion)

here is the code for the add button:

void CtestDlg::OnBnClickedMybuttonadd()
{
    CString str;
    UpdateData();
    str = m_myEditBox;
    UpdateData(FALSE);
    m_myListBox.AddString(str);
}

Answer 1

The type of m_myEditBox is CEdit.

You cannot assign a string from a CEdit objet by using the = operator.

Try this:

m_myEditBox.GetWindowText(str);

instead of:

str = m_myEditBox;

Answer 2

There is no off the helf conversion b/n CEdit to CString , please use this

int lc = m_myEditBox.GetLineCount();    

CString strLine;
CStringArray arr;

for (int i = 0; i < lc ; i++)
{
    int len = m_myEditBox.LineLength(m_myEditBox.LineIndex(i));
    m_myEditBox.GetLine(i, strLine.GetBuffer(len), len);
    strLine.ReleaseBuffer(len);

    m_myListBox.Add(strLine);
}