Question

I am writing an app that ultimately wants to send some XML via email.

I have the mailto/URL thing sussed, thanks to various links on the interweb, including Brandon and Simon Maddox.

So I can send emails with the xml formatted using square brackets ([ ]), rather than the usual angle brackets (< >). But when I send angle brackets, with the XML mangled using the stringByAddingPercentEscapesUsingEncoding call, It treats it as HTML and just prints the values.

If change them to "& lt;" and "& gt;" then it totally strips the XML out… (I know there should not be a space after the & – but the SO formatter turns them into <,>…)

I tried adding some HTML in front to see if that helped, to no avail.

I don’t suppose anyone has done this?

Perhaps in-app email is the easy route for me to go… must look into that.

Thanks in advance.

Answer 1

The following code worked for me… I have SIP message data containing <> that needed escaping.

/* remember to call urlEscapeStringDone to free the malloced string.. */
char *urlEscapeString(char *str)
{
    int i, l;
    char *escStr;

    escStr = malloc(strlen(str)*3 + 1);
    if(!escStr) return NULL;

    memset(escStr, 0, strlen(str)*3);

    l = strlen(escStr);
    for(i = 0; i < strlen(str); i++)
    {
        char c = str[i];

        /* < and > handling for HTML interpreters.. (apple mail) */
        if(c == '<')
        {
            strcat(escStr, "%26lt%3b");
            l += 8;
        }
        else if(c == '>')
        {
            strcat(escStr, "%26gt%3b");
            l += 8;
        }
        else if(must_escape(c))
        {
            char tmp[3];

            sprintf(tmp, "%02x", (unsigned) c);
            escStr[l] = '%'; l++;
            escStr[l] = tmp[0]; l++;
            escStr[l] = tmp[1]; l++;
        }
        else
        {
            escStr[l] = str[i];
            l++;
        }
    }

    printf("escaped: %s\n", escStr);

    return escStr;
}

void urlEscapeStringDone(char *str)
{
    if(str) free(str);
}

int must_escape(char c)
{
    char *allowedChars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789._";

    if(!strchr(allowedChars, c)) return 1;
    return 0;
}