I'm a student making a game for a summative, and an error is popping up that I have no idea how to solve it. I'm a bit of a coding newbie so any help is appreciated!
I've tried changing the variables in the for statement, but still no luck.
for (let i=0; i<4; i+=1){
if (dotCollideColour[i]!=dotColour[i]){
dotCollide = false;
break;
}
}
The error I'm getting is:
Uncaught TypeError: Cannot read property '0' of undefined.
I'd just like to be able to get this error to go away while still having my game to work. I'm fine sharing my full code if it's needed to help.
Edit the condition to dotCollideColour && dotColour && dotCollideColour[i] != dotColour[i] to make the error go away for now. But you still will have to correct the issue in a near future.
The issue being that dotCollideColour or/and dotColour is undefined.
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I had to initially put the behind the body because it was refreshing the page.
Now i'm running into this error "app.js:33 Uncaught TypeError: Cannot read property 'appendChild' of null
at HTMLButtonElement.addTodo"
Your selector is .todo-List, yet all your other class names don't use any upper-case characters, and your HTML shows class="todo-list" (list, not List!) as well.
So, I'd assume that this is a typo and should actually be todo-list with lower-case l, so you should change the line 4 to const todoList = document.querySelector('.todo-list').
The fact that you asked about the "message" of Cannot read property "appendChild" of null though sounds to me as if you didn't understand the error message. Please take the time to review this article and take a quick squiz at how to use a debugger. Especially the latter is a tremendously important skill that will help you trace back those issues yourself. I'm sure, had you realized that the issues comes from line 4, you'd eventually have discovered that the selector is wrong.
We have to use VBScript as an embedded script engine in our Hospital Information System.
When we use nothing to set the value of a control (textbox/checkbox/...) it worked always fine. Since somepoint it sets now the textbox to "?>".
item("TEXTBOX").value = nothing ' Leads to -> "?>"
It is not completly clear what causes this, maybe a windows update is responsible, every rollup ~ since KB3212646 Win7 2017-01 seems to cause this error.
My Question is now, has someone else also seem this error, so that it is clear that MS causes this error or is our HIS publisher responsible for not handling nothing correct.
I know setting a textbox to Nothing is not best practice instead "" should be better, but since the item object could be more the just a textbox e.g. a combobox/checkbox this seems, from an objectoriented perpsective, better. Or am I completly wrong?
Following #Ansgar comment, you should apparently change everywhere you have = nothing to = "" in your example
item("TEXTBOX").value = ""
Beware to keep the nothing if you have the Set keyword in left
Set some_object = Nothing
So I'm doing some business logic and want to run some code that goes like
select id from blah where foo = 1234 for update nolock
This code throws a DataMapper::SQLError when the corresponding row in blah is locked. This is desirable behavior; I would like to catch this error and use it to inform my application logic. But I want to re-throw any other SQL errors, because they're different than the case I'm programming for, and catching them in the same way would be wrong.
The error object returned has a string error message, and a numeric code (50463045). It seems like comparing on the numeric code would be great, but I don't want to embed the constant 50463045 in my code without some modicum of understanding of how the heck it was determined. Notably, the Postgres manual suggests that the error code for this state is 55P03, and that doesn't seem to be the same thing. I don't have any idea how much I can trust this magic number, and how to determine it except for experimentally, so I'm not really comfortable with using it.
How is the error code determined?
The Internet was distressingly unhelpful, since searching for stuff about DataObjects SQL errors seems to mostly return problems with other software raising the errors, not information on the errors themselves... but after locating the right source code and browsing around through the source code I finally located do_postgres.c:
void do_postgres_raise_error(VALUE self, PGresult *result, VALUE query) {
const char *message = PQresultErrorMessage(result);
char *sql_state = PQresultErrorField(result, PG_DIAG_SQLSTATE);
int postgres_errno = MAKE_SQLSTATE(sql_state[0], sql_state[1], sql_state[2], sql_state[3], sql_state[4]);
PQclear(result);
data_objects_raise_error(self, do_postgres_errors, postgres_errno, message, query, rb_str_new2(sql_state));
}
Notice how a 5-character state is passed to MAKE_SQLSTATE... and then also passed to data_objects_raise_error itself. I couldn't track down where MAKE_SQLSTATE is defined to figure out what crazy manipulations are going on to make this integer, but it appears I can just use the error object's .sqlstate property directly, and make my condition e.sqlstate == '55P03'.
I am having a very strange problem. First, the code.
Private Function ProcessRecord(ByVal rsDocs As ADODB.Recordset) As Variant
Dim rsTemp As ADODB.Recordset
rsTemp = rsDocs
rsDocs = RemoveDuplicateDocs(rsTemp)
Exit Function
The error is occurring on the second line of the function, where rsTemp is set equal to rsDocs. It's saying: "Compile error: Invalid use of property". I've looked for information on this error elsewhere, and all the reports are cases where people either forgot an equal sign, or incorrectly added the "Set" command to the beginning of the line of code. This error makes no sense to me, because it was compiling fine before, and the changes I've made to this project are not even in the class that throwing the error. The code here is identical to the way it was before. Has anyone ever seen an error like this pop up for what seems to be no good reason? Thanks!
You need to use
set rsTemp = rsDocs
since rsTemp is an object.
I keep getting an expected identifier error at this line in my code =/
$.fn.myPlugin = $.myPlugin;
any idea why this might be happening?
Actually I just found the answer here:
http://www.ventanazul.com/webzine/articles/javascript-expected-identifier-error-internet-explorer
Some coffees later I found the
offending code was:
var class =
$(this).parent().attr('class');
Yep, class seems to be a reserved word
in Internet Explorer, thanks again
Microsoft for making web developers'
lives so difficult.
I just changed the variable name to
fix the error, something like this:
var tabClass =
$(this).parent().attr('class');