QFileDialog 檔案讀取
===

## EX1

讀取`png`並顯示

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *


class filedialogdemo(QWidget):
    def __init__(self, parent=None):
        super(filedialogdemo, self).__init__(parent)

        layout = QVBoxLayout()
        self.btn = QPushButton("QFileDialog static method demo")
        self.btn.clicked.connect(self.getfile)

        layout.addWidget(self.btn)
        self.le = QLabel("Hello")

        layout.addWidget(self.le)
        
        self.setLayout(layout)
        self.setWindowTitle("File Dialog demo")

    def getfile(self):
        fname = QFileDialog.getOpenFileName(self, 'Open file',
                                            '/Users/', "Image files (*.png)")
        print(fname[0], ",", fname[1])
        img = QPixmap()
        img.load(fname[0])
        self.le.setPixmap(img)


def main():
    app = QApplication(sys.argv)
    ex = filedialogdemo()
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

## EX2

讀取不同類型\(文件夾、單一檔案、多檔案\)

import sys
import os
from PyQt5.QtWidgets import *

class MainForm(QWidget):
    def __init__(self, name = 'MainForm'):
        super(MainForm,self).__init__()
        self.setWindowTitle(name)
        self.cwd = os.getcwd() # 获取当前程序文件位置
        self.resize(300,200)   # 设置窗体大小
        
        # btn 1
        self.btn_chooseDir = QPushButton(self)
        self.btn_chooseDir.setObjectName("btn_chooseDir")
        self.btn_chooseDir.setText("选择文件夹")

        # btn 2
        self.btn_chooseFile = QPushButton(self)
        self.btn_chooseFile.setObjectName("btn_chooseFile")
        self.btn_chooseFile.setText("选取文件")

        # btn 3
        self.btn_chooseMutiFile = QPushButton(self)
        self.btn_chooseMutiFile.setObjectName("btn_chooseMutiFile")
        self.btn_chooseMutiFile.setText("多文件选择")

        # btn 4
        self.btn_saveFile = QPushButton(self)
        self.btn_saveFile.setObjectName("btn_saveFile")
        self.btn_saveFile.setText("文件保存")

        # 设置布局
        layout = QVBoxLayout()
        layout.addWidget(self.btn_chooseDir)
        layout.addWidget(self.btn_chooseFile)
        layout.addWidget(self.btn_chooseMutiFile)
        layout.addWidget(self.btn_saveFile)
        self.setLayout(layout)


        # 设置信号
        self.btn_chooseDir.clicked.connect(self.slot_btn_chooseDir)
        self.btn_chooseFile.clicked.connect(self.slot_btn_chooseFile)
        self.btn_chooseMutiFile.clicked.connect(self.slot_btn_chooseMutiFile)
        self.btn_saveFile.clicked.connect(self.slot_btn_saveFile)



    def slot_btn_chooseDir(self):
        dir_choose = QFileDialog.getExistingDirectory(
            self,
            "选取文件夹",
            self.cwd    # 起始路径
        )

        if dir_choose == "":
            print("\n取消选择")
            return

        print("\n你选择的文件夹为:")
        print(dir_choose)


    def slot_btn_chooseFile(self):
        fileName_choose, filetype = QFileDialog.getOpenFileName(
            self,
            "选取文件",
            self.cwd, # 起始路径
            "All Files (*.png);;Text Files (*.txt)" # 设置文件扩展名过滤,用双分号间隔
        )

        if fileName_choose == "":
            print("\n取消选择")
            return

        print("\n你选择的文件为:")
        print(fileName_choose)
        print("文件筛选器类型: ",filetype)


    def slot_btn_chooseMutiFile(self):
        files, filetype = QFileDialog.getOpenFileNames(
            self,
            "多文件选择",
            self.cwd, # 起始路径
            "All Files (*);;PDF Files (*.pdf);;Text Files (*.txt)"
        )

        if len(files) == 0:
            print("\n取消选择")
            return

        print("\n你选择的文件为:")
        for file in files:
            print(file)
        print("文件筛选器类型: ",filetype)


    def slot_btn_saveFile(self):
        fileName_choose, filetype = QFileDialog.getSaveFileName(
            self,
            "文件保存",
            self.cwd, # 起始路径
            "All Files (*);;Text Files (*.txt)"
        )

        if fileName_choose == "":
            print("\n取消选择")
            return

        print("\n你选择要保存的文件为:")
        print(fileName_choose)
        print("文件筛选器类型: ",filetype)

if __name__=="__main__":
    app = QApplication(sys.argv)
    mainForm = MainForm('测试QFileDialog')
    mainForm.show()
    sys.exit(app.exec_())

## Ref.

[https://www.tutorialspoint.com/pyqt5/pyqt5\_qfiledialog\_widget.htm](https://www.tutorialspoint.com/pyqt5/pyqt5\_qfiledialog\_widget.htm)

[https://blog.csdn.net/humanking7/article/details/80546728](https://blog.csdn.net/humanking7/article/details/80546728)

###### tags: `PyQt5`