javascript - Confusion on data returned from controller to Ajax -


i have ajax call in 1 of coffee scripts goes method of controller. ajax call looks this:

auto = ->   $.ajax     url  : '<method_name>'     type : 'post'     data :       <variable_name>: $('element').val()     success: (data, status, response) ->       alert('pass')     error: ->      alert('fail')

my method in controller looks as:

def method   ...   ...   <book> object can invalid object.   respond_to |format|     format.json { render json: {book: {title: title}} }   end end

now, 'book/title'(from controller) should available in coffee script through 'data' variable(in coffee script). right?

my question when go in 'error' block(for coffee scripts)? can see 'book' object null(in controller) still coming in 'success' block(in coffee script).. thought if json objects null, come 'error' block.

whenever ajax fails (for eg. if there's routing error or error in controller's method etc) comes error block. here method works fine, without error, no matter book null or not. can check in controller if book object null, return flag , check variable in ajax success. example:

def method   ...   ...   <book> object can invalid object.   if book.nil?      format.json { render json: {is_data_null: true} }   else     respond_to |format|       format.json { render json: {book: {title: title}} }     end   end end

and in ajax success block, can check flag.


Comments

Post a Comment

Popular posts from this blog

cakephp - simple blog with croogo -

i not problem, made simple blog in croogo, problem is not adding or modifying or delete, because arabic language ?? function add in controller `public function admin_add() { $this->set('title_for_layout', __('add part')); if (!empty($this->request->data)) { $this->part->create(); if ($this->part->save($this->request->data)) { $this->session->setflash(__('the part has been saved'), 'default', array('class' => 'success')); $this->redirect(array('action' => 'index'));//, $this->part->id)); } else { $this->session->setflash(__('the part not saved. please, try again.'), 'default', array('class' => 'error')); } } }` => model `class part extends appmodel { public $name = 'part'; var $belongst...
Read more

How to group boxplot outliers in gnuplot -

i have large set of data points. try plot them boxplot, of outliers exact same value , represented on line beside each other. found how set horizontal distance between outliers in gnuplot boxplot , doesn't much, apparently not possible. is possible group outliers together, print 1 point , print number in brackets beside indicate how many points there are? think make more readable in graph. for information, have 3 boxplots 1 x value , times 6 in 1 graph. using gnuplot 5 , played around pointsize, doesn't reduce distance anymore. hope can help! edit: set terminal pdf set output 'dat.pdf' file0 = 'dat1.dat' file1 = 'dat2.dat' file2 = 'dat3.dat' set pointsize 0.2 set notitle set xlabel 'x' set ylabel 'y' header = system('head -1 '.file0); n = words(header) set xtics ('' 1) set [i=1:n] xtics add (word(header, i) i) set style data boxplot plot file0 using (1-0.25):1:(0.2) boxplot lw 2 lc rgb '#8b0000...
Read more

bash - Performing variable substitution in a string -

i have string contains use of variable, , i'd substitute variable's value string. right best have is #!/bin/bash foo='$name; echo bar' name="the name" expanded="$(eval echo "$foo")" echo "$expanded" which has obvious defects: prints the name bar while i'd print the name; echo bar instead of eval can bash's regex matching bash's string replacement: foo='$name; echo bar' name="the name" [[ "$foo" =~ \$([[:alnum:]]+) ]] && s="${!bash_rematch[1]}" && expanded="${foo/\$${bash_rematch[1]}/$s}" echo "$expanded" name; echo bar
Read more