Simple Form

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Simple Form
ltform action"/x/y/z" method"POST"gt Value1
ltinput type"text" name"value1"/gtltbr /gt
Value2 ltinput type"text" name"value2"/gt
ltinput type"submit" value"Submit"/gt lt/formgt
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Rails Form Helpers
Name of modelclass (Student)
Name of variable containing data (_at_student)
lt form_for(student, url gt action gt
modify, id gt_at_student.id) do form gt
lttable class"form"gt lttrgt lttd
class"label"gtNamelttdgt lttdgtlt
form.text_field(name) gtlttdgt lt/trgt lttrgt
lttd class"label"gtDate of birthlttdgt
lttdgtlt form.text_field(birth) gtlttdgt lt/trgt
... lttablegt lt submit_tag "Modify
Student" gt lt end gt
Initial value will be_at_student.name
Text to displayin submit button
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Post Action Method
Hash with all of form data
def modify _at_student Student.find(paramsid)
if _at_student.update_attributes(paramsstudent)
then redirect_to(action gt show) else
render(action gt edit) end end
Redirects on success
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Validation
Custom validation method
class Student lt ActiveRecordBase def
validate if (gpa lt 0) (gpa gt 4.0) then
errors.add(gpa, "must be between 0.0 and
4.0") end end validates_format_of
birth, with gt /\d\d\d\d-\d\d-\d\d/,
message gt "must have format YYYY-MM-DD end
Built-in validator
Saves error info
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Error Message Helper
lt error_messages_for(student)gt lt
form_for(student, url gt action gt modify,
id gt_at_student.id) do form gt ... lt end gt
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