import streamlit as st

st.title('代码一例子')
count = 0

increment = st.button('增加')
if increment:
    count += 1

st.write('Count = ', count)

# 这个代码执行后，不管你咋按那个按钮，count都是1。

import streamlit as st

# 检查 'key' 是否存在于 session_state 中
# 如果不存在，则初始化之 
if 'key' not in st.session_state:
    st.session_state['key'] = 'value'

# 另一种语法
if 'key' not in st.session_state:
    st.session_state.key = 'value'

import streamlit as st

st.title('代码一改为代码二')
# 检查 'count' 是否在 session_state中
if 'count' not in st.session_state:
    st.session_state.count = 0

increment = st.button('增加')
if increment:
    st.session_state.count += 1

st.write('Count = ', st.session_state.count)

import streamlit as st

st.title('采用回调来更改代码一')
# 检查 'count' 是否在 session_state中
if 'count' not in st.session_state:
    st.session_state.count = 0

# 定义函数，一会儿就要回调它
def increment_counter():
    st.session_state.count += 1

# 在 st.button里回调函数 increment_counter()
st.button('Increment', on_click=increment_counter)

st.write('Count = ', st.session_state.count)

import streamlit as st

st.title('回调函数有参数')
if 'count' not in st.session_state:
    st.session_state.count = 0

increment_value = st.number_input('输入一个数值', value=0, step=1)

# 函数有参数
def increment_counter(increment_value):
    st.session_state.count += increment_value
# 采用 args 把参数导入
increment = st.button('Increment', on_click=increment_counter,
    args=(increment_value, ))

st.write('Count = ', st.session_state.count)

import streamlit as st

st.title('回调参数用 kwargs 传递参数')
if 'count' not in st.session_state:
    st.session_state.count = 0

def increment_counter(increment_value=0):
    st.session_state.count += increment_value

def decrement_counter(decrement_value=0):
    st.session_state.count -= decrement_value

st.button('Increment', on_click=increment_counter,
    kwargs=dict(increment_value=5))

st.button('Decrement', on_click=decrement_counter,
    kwargs=dict(decrement_value=1))

st.write('Count = ', st.session_state.count)

import streamlit as st

if "celsius" not in st.session_state:
    # set the initial default value of the slider widget
    st.session_state.celsius = 50.0

st.slider(
    "Temperature in Celsius",
    min_value=-100.0,
    max_value=100.0,
    key="celsius" # 采用 key 把slider小部件中的值与全局变量celsius关联
)

# This will get the value of the slider widget
st.write(st.session_state.celsius)

from flask import Flask
from flask import g, request

app=Flask(__name__)

@app.before_request
def span_num_init():
	g.start_num = 0 # 定义g变量
	g.span_mum = 5 # 定义g变量

@app.route("/fun1")
def fun1():
    g.start_num=9
    g.span_num=16

@app.route("/fun2")
def fun2():
    print("start_num=",g.start_num) # 此处start_num又变为0
    print("span_num=",g.span_num]) # 此处start_num又变为5

def get_option_item():
    item = ["项目1"，"项目2"，"项目3"，"项目4"，"项目5"，"项目6"，"项目7"，]
    return item
#视图1
@app.route(/index1)
def index1():
    item=get_option_item()
    return render_template("index1.html", item=itme)
....
#视图n
@app.route(/index_n)
def index_n():
    item=get_option_item()
    return render_template("indexn.html", item=itme)

# current_app对象是一个定义在应用上下文中的代理
from flask import current_app
app=Flask(__name__)

# 函数用@app.context_processor装饰器修饰，它是一个上下文处理器，它的作用是在模板被渲染前运行其所修饰的函数，并将函数返回的字典导入到模板上下文环境中，与模板上下文合并。
@app.context_processor
def get_option_item():
    item = ["项目1"，"项目2"，"项目3"，"项目4"，"项目5"，"项目6"，"项目7"，]
    return dict(item=item) #注意是字典
# 视图函数不用再调用了
#视图n
@app.route(/index_n)
def index_n():
    # item=get_option_item()
    return render_template("indexn.html")

with st.form("my_form"):
    st.write("Inside the form")
    slider_val = st.slider("Form slider")
    checkbox_val = st.checkbox("Form checkbox")

    # 每一个form必须有一个 submit 按钮.
    submitted = st.form_submit_button("Submit")
    if submitted:
        st.write("slider", slider_val, "checkbox", checkbox_val)

st.write("己通退了表单j")

form23 = st.form("my_form")
form23.slider("Inside the form")
st.slider("在此表单外面了")

# 增加一个submit按钮到此表单:
form23.form_submit_button("Submit")

class MockCreate(Form):
    user_email = StringField("email address",[validators.Email()])
    api = StringField("api",[Required()])
    submit = SubmitField("Submit")
    code = IntegerField("code example: 200",[Required()])
    alias = StringField("alias for api")
    data = TextAreaField("json format",[Required()])


@app.route("/mockservice",methods=['GET','POST'])
def MockController():
    form = MockCreate()
    code = form['code']
    api = form['api']
    return render_template("testf.html",api=api,data=code)

from flask import Flask
from flask import render_template
from flask_wtf import FlaskForm
from wtforms.fields import (StringField, PasswordField, DateField, BooleanField,
                            SelectField, SelectMultipleField, TextAreaField,
                            RadioField, IntegerField, DecimalField, SubmitField)
from wtforms.validators import DataRequired, InputRequired, Length, Email, EqualTo, NumberRange


app = Flask(__name__)
app.secret_key = 'asdfs'


class WtfForm(FlaskForm):
    # StringField 文本输入框，必填，用户名长度为4到25之间，占位符
    username = StringField('用户名：', validators=[Length(min=4, max=25)], render_kw={'placeholder': '请输入用户名'})

    # Email格式
    email = StringField('邮箱地址：', validators=[Email()], render_kw={'placeholder': '请输入邮箱地址'})

    # PasswordField，密码输入框，必填
    password = PasswordField('密码：', validators=[DataRequired()], render_kw={'placeholder': '请输入密码'})

    # 确认密码，必须和密码一致
    password2 = PasswordField('确认密码：', validators=[InputRequired(), EqualTo('password', '两次密码要一致')])

    # IntegerField，文本输入框，必须输入整型数值，范围在16到70之间
    age = IntegerField('年龄：', validators=[NumberRange(min=16, max=70)])

    # DecimalField，文本输入框，必须输入数值，显示时保留一位小数
    height = DecimalField('身高(cm):', places=1)

    # DateField，文本输入框，必须输入是"年-月-日"格式的日期
    birthday = DateField('出生日期：', format='%Y-%m-%d')

    # RadioField，单选框，choices里的内容会在ul标签里，里面每个项是(值，显示名)对
    gender = RadioField('性别：', choices=[('0', '男'), ('1', '女')], validators=[DataRequired()])

    # SelectField，下拉单选框，choices里的内容会在Option里，里面每个项是(值，显示名)对
    job = SelectField('职业：', choices=[
        ('teacher', '教师'),
        ('doctor', '医生'),
        ('engineer', '工程师'),
        ('lawyer', '律师')
    ])

    # Select类型，多选框，choices里的内容会在Option里，里面每个项是(值，显示名)对
    hobby = SelectMultipleField('爱好：', choices=[
        ('0', '吃饭'),
        ('1', '睡觉'),
        ('2', '敲代码')
    ])

    # TextAreaField，段落输入框
    description = TextAreaField('自我介绍：', validators=[InputRequired()], render_kw={'placeholder': '例：小明，18岁，未婚找女友'})

    # BooleanField，Checkbox类型，加上default='checked'即默认是选上的
    accept_terms = BooleanField('是否接受上述条款', default='checked', validators=[DataRequired()])

    # SubmitField，Submit按钮
    submit = SubmitField('提交')


@app.route('/', methods=['POST', 'GET'])
def index():
    form = WtfForm()
    return render_template('wtf.html', form=form)

if __name__ == "__main__":
    app.run(debug=True)

from flask import Flask,request,render_template

app=Flask(__name__)

app.secret_key = '就得是要一个key'   # 必须有
app.config['SESSION_TYPE'] = 'filesystem' # 必须有

start_num=0
span_num=5

@app.route("/fun1")
def fun1():
    start_num=9
    span_num=16

@app.route("/fun2")
def fun2():
    print("start_num=",start_num) #此处start_num又变为0
    print("span_num=",span_num]) #此处start_num又变为5

from flask import Flask,request,render_template
from flask import session

app=Flask(__name__)

app.secret_key = '我的key'
app.config['SESSION_TYPE'] = 'filesystem'

session["start_num"]=0
session["span_num"]=5

@app.route("/fun1")
def fun1():
    session["start_num"]=9
    session["span_num"]=16

@app.route("/fun2")
def fun2():
    print("session["start_num"]",session["start_num"]) #此处session["start_num"]又变为9
    print("session["span_num"]",session["span_num"]) #此处session["start_num"]又变为16