How to add a floating prompt to the Modal dialog box?

topic description

my sending address needs to be prompted at the top. How to realize the floating prompt function in the dialog box?

sources of topics and their own ideas

related codes

/ / Please paste the code text below (do not replace the code with pictures)

<Modal  v-model="visible" :title="itemtitle" width="50" :styles="{top: "55px"}" :mask-closable="false" :loading="managerloading"
>
    <i-form ref="modifyForm" v-if="visible" :model="dockingInfo" label-position="right" :label-width="80" :rules="ruleInline" inline>
        <form-Item prop="SYSNAME" label="">
            <i-input type="text" v-model="dockingInfo.SYSNAME" style="width: 170px"></i-input>
        </form-Item>

        <form-Item prop="SYSTYPE" label="">
            <i-combox  dict="EXTLX" v-model="dockingInfo.SYSTYPE"  valuefield="SYSTYPE" textfield="SYSTYPE_TEXT" style="width: 170px"></i-combox>
        </form-Item>

        <form-Item prop="SERVERID" label="">
            <i-input type="text" v-model="dockingInfo.SERVERID" number style="width: 170px"></i-input>
        </form-Item>

        <form-Item prop="ORGS" label="" style="width: 95%">
            <Scroll :height="150">
                <checkbox-group v-model="orgsSelected"  @on-change="orgchange">
                    <Checkbox  v-for="(ORGS,index) in orgsList" :value="ORGS.ORGNAME" :key="ORGS.ORGID" :label="ORGS.ORGID">
                        <span>{{ORGS.ORGID}}- {{ORGS.ORGNAME}}</span>
                    </Checkbox>
                </checkbox-group>
            </Scroll>
        </form-Item><br>

        <form-Item prop="DISPATCH" label="" >
            <i-combox  dict="ESJXFFS" v-model="dockingInfo.DISPATCH" valuefield="DISPATCH" textfield="DISPATCH_TEXT"  style="width: 170px"></i-combox>
        </form-Item><br>

        <form-Item prop="LINKSTR" label="" style="width: 95%">
            <i-input type="text" v-model="dockingInfo.LINKSTR" :placeholder="dockingInfo.DISPATCH==0?":-sharpurl-sharp-sharp":":D:\\""></i-input>
        </form-Item>
    </i-form>
    <div slot="footer">
        <i-button type="primary" size="large" @click="connect("modifyForm")"></i-button>
        <i-button type="primary" size="large" @click="cancel("modifyForm")"></i-button>
        <i-button type="primary" size="large" @click="ok("modifyForm")"></i-button>
    </div>
</Modal>

what result do you expect? What is the error message actually seen?

problem description

Nov.19,2021
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