Mfc Rich Edit Control Image

A Rich Edit Control is a window in which the user can enter and edit text. The text can be assigned character and paragraph formatting, and can include embedded OLE objects. It is represented by CRichEditCtrl class. Here is the list of methods in CRichEditCtrl class. A Rich Edit Control That Displays Bitmaps and Other OLE Objects. I needed a rich edit control that could display bitmaps. If you use ole to place an image in.

When inserting Rich Text Formatted text into the control there are two approaches you can take. Insert the control into the text, then select it and then format it. This can result in a lot of code and not very clean code at that.

The other approach is that you can format the text into a CString variable and insert that in one fell swoop. This is much faster and reduces the number of lines of code. Step 1: Define the EditStreamCallBack() callback function When we stream in data into the rich edit control, we have to define a callback function that is called by the control to supply the actual data. This callback function can be called repeatedly by control till the function indicates that there is no more data. One of the arguments passed to the callback function is an application defined value. We will use this value to pass in a CString object's address. The second argument is the address of the buffer where the data is to be written by the function, the third argument specifies the number of bytes requested by the rich edit control.

The final argument is pointer to a long value. The callback function should set this value to the number of bytes actually copied to the buffer. If this value is less than the number of bytes requested by the control, then the control assumes that there is no more text available and it will stop calling this function.

We have defined the EditStreamCallBack() function as a file static function. This makes the function local to the file. We can define a function with the same name in another file. We could have defined this function as a class function but it would have had to be a class static function. Note the type CALLBACK.

Forgetting to specify this can be cause for major headaches.