12.4 HTML_TRUNC Function

The HTML_TRUNC function escapes html and limits the returned string to p_length bytes. This function returns the first p_length bytes of an input clob and escapes them. You can use this function if the input clob might be too large to fit in a varchar2 variable and it is sufficient to only display the first part of it.

Syntax

APEX_ESCAPE.HTML_TRUNC (
    p_string IN CLOB,
    p_length IN NUMBER DEFAULT 4000 )
    return VARCHAR2;

Parameters

Example

This example generates a html list of of titles and text bodies. Html entity attributes are escaped with HTML_ATTRIBUTE, whereas normal text is escaped with HTML and HTML_TRUNC.

begin 
    htp.p('<ul>'); 
    for l_data in ( select title, cls, body 
        from my_topics ) 
    loop 
    sys.htp.p('<li><span class="'||
        apex_escape.html_attribute(l_data.cls)||'">'|| 
        apex_escape.html(l_data.title)||'</span>'); 
    sys.htp.p(apex_escape.html_trunc(l_data.body)); 
    sys.htp.p('</li>'); 
    end loop; 
    htp.p('</ul>'); 
end;