汇编语言函数2循环

Question

我试图弄清楚如何使用我的光标在一个字符串中循环一个字符。
我制作的程序能够在字符串中获取某个索引。
但是，我怎么能一次遍历整个字符串一个字符？

title Hello World Program (hello3.asm)

;
; This is the sample program on page 572 of your text with little modification
;It utilizes Dos service 40h.
;

.model small
.data
    message db "Hello, Dos Here!",0dh,0ah,'$'


.code
main proc
    mov ax, @data
    mov ds, ax
    mov cx, 5
L1:
    mov ah, 2
    mov dl, message
    int 21h

loop L1
    mov ax, 4c00h
    int 21h
main endp
end 

`

Answer 1

正如@Michael所建议的那样，您需要将字符串的地址放在寄存器中，例如SI，然后一次增加.model small .data message db "Hello, Dos Here!",0dh,0ah,'$' .code main proc mov ax, @data mov ds, ax ; mov cx, 5 ;<=== WE DON'T NEED CX BECAUSE WE AREN'T ; USING THE LENGTH OF THE STRING, WE ; ARE USING THE '$' CHAR. mov si, offset message ;<=== SI POINTS TO FIRST CHARACTER OF STRING. L1: ;CHECK IF '$' (LAST CHAR) IS THE CURRENT CHAR. mov dl, [si] ;<=== CURRENT CHARACTER TO PRINT. cmp dl, '$' ;<=== IF CURRENT CHAR IS '$'... je finish ;<=== ... JUMP TO FINISH. ;PRINT CHAR IN DL. mov ah, 2 int 21h ;loop L1 ;<=== WE DON'T NEED LOOP BECAUSE ; WE ARE NOT USING CX. inc si ;<=== NEXT CHAR OF THE STRING. jmp L1 ;<=== REPEAT. finish: mov ax, 4c00h int 21h main endp end 一个字节（一个字符）。当达到char'$'时，循环必须完成：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>........</groupId>
    <artifactId>.............</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <build>
        <directory>target</directory>
        <outputDirectory>target/classes</outputDirectory>
        <finalName>${artifactId}-${version}</finalName>
        <testOutputDirectory>target/test-classes</testOutputDirectory>
        <sourceDirectory>src/main/java</sourceDirectory>
        <scriptSourceDirectory>src/main/scripts</scriptSourceDirectory>
        <testSourceDirectory>src/test/java</testSourceDirectory>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
            </resource>
        </resources>
        <testResources>
            <testResource>
                <directory>src/test/resources</directory>
            </testResource>
        </testResources>
        <plugins>

            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.3</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>

        </plugins>
    </build>


    <!-- <build> <sourceDirectory>src</sourceDirectory> <resources> <resource> 
        <directory>src</directory> <excludes> <exclude>**/*.java</exclude> </excludes> 
        </resource> </resources> <plugins> <plugin> <artifactId>maven-compiler-plugin</artifactId> 
        <version>3.3</version> <configuration> <source>1.8</source> <target>1.8</target> 
        </configuration> </plugin> </plugins> </build> -->
    <properties>
        <java.version>1.8</java.version>
        <spring-framework.version>4.2.2.RELEASE</spring-framework.version>
        <hibernate.version>4.3.11.Final</hibernate.version>
        <kundera.version>3.3</kundera.version>
        <jackson.version>2.7.0</jackson.version>
    </properties>
    <dependencies>
        <!-- <dependency> <groupId>com.impetus.kundera.client</groupId> <artifactId>kundera-cassandra-ds-driver</artifactId> 
            <version>3.3</version> <exclusions> <exclusion> <groupId>org.slf4j</groupId> 
            <artifactId>slf4j-log4j12</artifactId> </exclusion> <exclusion> <groupId>log4j</groupId> 
            <artifactId>log4j</artifactId> </exclusion> </exclusions> </dependency> -->

        <dependency>
          <groupId>org.javassist</groupId>
            <artifactId>javassist</artifactId>
            <version>3.18.1-GA</version>
        </dependency>   
        <dependency>
            <groupId>com.impetus.kundera.client</groupId>
            <artifactId>kundera-cassandra</artifactId>
            <version>${kundera.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <!-- <dependency> <groupId>com.impetus.client</groupId> <artifactId>kundera-cassandra-jpa2.1</artifactId> 
            <version>0.1</version> <exclusions> <exclusion> <groupId>org.slf4j</groupId> 
            <artifactId>slf4j-log4j12</artifactId> </exclusion> <exclusion> <groupId>log4j</groupId> 
            <artifactId>log4j</artifactId> </exclusion> </exclusions> </dependency> -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>${hibernate.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <!-- <dependency>
              <groupId>org.springframework.boot</groupId>
              <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency> -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>${hibernate.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.codehaus.jackson</groupId>
            <artifactId>jackson-core-asl</artifactId>
            <version>1.9.2</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.codehaus.jackson</groupId>
            <artifactId>jackson-mapper-asl</artifactId>
            <version>1.9.2</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>${jackson.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <!-- Note: core-annotations version x.y.0 is generally compatible with 
                (identical to) version x.y.1, x.y.2, etc. -->
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>${jackson.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>${jackson.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <!-- <dependency> <groupId>com.impetus.kundera.core</groupId> <artifactId>kundera-core</artifactId> 
            <version>${kundera.version}</version> </dependency> -->
        <!-- <dependency> <groupId>com.impetus.client</groupId> <artifactId>kundera-cassandra-jpa2.1</artifactId> 
            <version>0.1</version> </dependency> -->

        <dependency>
            <groupId>com.impetus.kundera.client</groupId>
            <artifactId>kundera-rdbms</artifactId>
            <version>${kundera.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.antlr</groupId>
            <artifactId>antlr</artifactId>
            <version>3.5.2</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.antlr</groupId>
            <artifactId>antlr-runtime</artifactId>
            <version>3.5.2</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
                <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-starter-logging</artifactId>
            </exclusion>
            </exclusions>
        </dependency>
        <dependency>
         <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-log4j</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
            <scope>test</scope>
            <!-- <exclusions>
                <exclusion>
                    <groupId>org.apache.tomcat.embed</groupId>
                    <artifactId>tomcat-embed-websocket</artifactId>
                </exclusion>

                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-tomcat</artifactId>
                </exclusion>

            </exclusions>
 -->        </dependency>

    <!--    <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-dbcp2</artifactId>
            <version>2.1.1</version>
        </dependency> -->

        <!-- Unit Test  -->
        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-core</artifactId>
            <version>1.10.8</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.assertj</groupId>
            <artifactId>assertj-core</artifactId>
            <version>3.1.0</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.hamcrest</groupId>
            <artifactId>hamcrest-core</artifactId>
            <version>1.3</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.hamcrest</groupId>
            <artifactId>hamcrest-library</artifactId>
            <version>1.3</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.objenesis</groupId>
            <artifactId>objenesis</artifactId>
            <version>2.1</version>
            <scope>test</scope>
        </dependency>

        <!-- Quartz -->
        <dependency>
          <groupId>org.quartz-scheduler</groupId>
          <artifactId>quartz</artifactId>
          <version>2.2.1</version>
        </dependency>
        <dependency>
          <groupId>org.quartz-scheduler</groupId>
          <artifactId>quartz-jobs</artifactId>
          <version>2.2.1</version>
        </dependency>

        <!-- Spring AOP + AspectJ -->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
            <version>1.8.7</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-messaging</artifactId>
            <version>4.2.5.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
        </dependency>

        <!-- OpenWeatherMap -->
        <!-- <dependency>
            <groupId>org.bitpipeline.lib</groupId>
            <artifactId>owm-lib</artifactId>
            <version>2.1.3-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.2.3</version>
        </dependency>
        <dependency>
            <groupId>org.json</groupId>
            <artifactId>json</artifactId>
            <version>20090211</version>
        </dependency> -->

    </dependencies>
    <repositories>
        <repository>
            <id>kundera-release</id>
            <name>Kundera Release Repository</name>
            <url>http://kundera.googlecode.com/svn/maven2/maven-repo-release/</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>sonatype-nexus</id>
            <name>Kundera Public Repository</name>
            <url>https://oss.sonatype.org/content/repositories/releases</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>riptano</id>
            <name>riptano</name>
            <url>http://mvn.riptano.com/content/repositories/public</url>
        </repository>
        <repository>
            <id>ossrh</id>
            <url>https://oss.sonatype.org/content/groups/public/</url>
        </repository>
    </repositories>
    <dependencyManagement>
    <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>1.3.5.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>

                <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>log4j-over-slf4j</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>