Whenever I try doing the code myself, nothing shows up after I run the function, I'm wanting to add all the numbers from 'fkWynik'.
function mat_WypiszLiczbyNaturalne() {
var T = "";
T = document.getElementById('fkEdit').value;
if ((T.trim() != "") && (Number(T) > 0)) {
var S = "";
for (var I = 1; I < Number(T) + 1; I++) {
S = S + ", " + I.toString();
}
document.getElementById('fkWynik').value = S.substr(2) + " = ";
} else {
document.getElementById('fkWynik').value = "Prosze wprowadzic liczbe!";
}
}<html>
<body>
<FORM NAME="formularz1" ACTION="">
<TABLE BORDER="0">
<INPUT TYPE="number" ID="fkEdit" STYLE="height:24px; width:55px;">
<INPUT TYPE="button" ID="fkWykonaj" VALUE="Wykonaj" onClick="mat_WypiszLiczbyNaturalne();"> </TD>
</TR>
<TR><TD> <INPUT TYPE="text" ID="fkWynik" STYLE="width:545px; height:24px;" READONLY> </TD></TR>
</TABLE>
</FORM>
</body>
</html>The following should work if your HTML code contains an element with the property id="fkWynik"
function mat_WypiszLiczbyNaturalne() {
var elem = document.getElementById('fkEdit');
if(!elem) {
console.error("No element with id 'fkEdit' in the page.");
return;
}
var T = elem.value;
var value = "";
if (T && !isNaN(Number(T))) { // if T not null, not empty, not undefined, not 0 and is a number
var S = "";
for (var I = 1; I < Number(T) + 1; I++) {
S = S + ", " + I.toString();
}
value = S.substr(2) + " = ";
} else {
value = "Proszę wprowadzić liczbę!";
}
console.log("value: " + value);
document.getElementById('fkWynik').value = value;
}
mat_WypiszLiczbyNaturalne();
You need to add the numbers together and concat it to the string:
function mat_WypiszLiczbyNaturalne() {
var T = "";
T = document.getElementById('fkEdit').value;
if ((T.trim() != "") && (Number(T) > 0)) {
var S = "";
var total = 0
for (var I = 1; I < Number(T) + 1; I++) {
S = S + ", " + I.toString();
total += I;
}
document.getElementById('fkWynik').value = S.substr(2) + " = "+total.toString();
} else {
document.getElementById('fkWynik').value = "Prosze wprowadzic liczbe!";
}
}<html>
<body>
<FORM NAME="formularz1" ACTION="">
<TABLE BORDER="0">
<INPUT TYPE="number" ID="fkEdit" STYLE="height:24px; width:55px;">
<INPUT TYPE="button" ID="fkWykonaj" VALUE="Wykonaj" onClick="mat_WypiszLiczbyNaturalne();"> </TD>
</TR>
<TR><TD> <INPUT TYPE="text" ID="fkWynik" STYLE="width:545px; height:24px;" READONLY> </TD></TR>
</TABLE>
</FORM>
</body>
</html>