mainwindow.cpp

#include <QtCore/QFile>
#include <QtCore/QTextStream>
#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) {
    ui->setupUi(this);
    getTextFile();
}

MainWindow::~MainWindow() {
    delete ui;
}

void MainWindow::on_goButton_clicked() {
    QString word = ui->lineEdit->text();
    ui->textEdit->find(word, QTextDocument::FindWholeWords);

}

void MainWindow::getTextFile() {
    QFile myFile(":/file.txt");
    myFile.open(QIODevice::ReadOnly);

    QTextStream textStream(&myFile);
    QString line = textStream.readAll();
    myFile.close();

    ui->textEdit->setPlainText(line);
    QTextCursor textCursor = ui->textEdit->textCursor();
    textCursor.movePosition(QTextCursor::Start, QTextCursor::MoveAnchor, 1);
}